In 1941, genocide broke out in Croatia and Bosnia, and we still cannot explain why. During the spring of that year, Croatian fascists—the Ustasha—burst into Serbian homes, abducting hundreds of males over the age of 16 and executing them, usually in mass shootings. Weeks earlier, Hitler’s Germany had broken up the (Royal) Yugoslav

state and given control of the new Independent State of Croatia (NDH) to the Ustasha, but the Nazis did not order its members to kill anyone. As it was, Serbs and Croats had co-existed peacefully in Croatia since the sixteenth century, when the Habsburgs invited Serbian Orthodox settlers into the areas bordering Ottoman territory. If the 1941 massacres remain a riddle, their consequences are clear. In the early 1990s, during the dissolution of socialist Yugoslavia, Serbs, Croats and occasionally Muslims followed the same script enacted fifty years earlier: armed men broke into peaceful homes, dragged out all the adult males to murder them, and then expelled their families.

For this reason, the historian Slavko Goldstein has dubbed 1941 “the year that keeps returning.” Goldstein was born in Sarajevo in 1928, to a Jewish couple—a bookseller and his wife—who had moved to the region from Palestine. He was 13 when he saw the Ustasha killing Serbs in the Croatian town of Karlovac, where he grew up. On the night of May 5, Goldstein recalls, five members of the Ustasha youth movement abducted the heads of three Serbian households at gunpoint. He pays special attention to one of the kidnapped men, a lawyer named Milan Vujicic, who had married into a prominent Croatian family, become part of the city’s elite and courageously opposed the dictatorship of Yugoslav King Alexander. Such was the esteem for Vujicic in Croatian circles that Governor Ivan Subasic wanted to appoint him a deputy when Croatia gained de facto autonomy within Yugoslavia in 1939. Two years later, those facts amounted to his death sentence. The bodies of Vujicic and the other two Serbs were discovered in a shallow grave. The message was clear: there would be no compromise under the Ustasha, especially with Serbs, whose ethnicity was suspect and therefore threatening. Vujicic, like his father and forefathers a native of Croatia, spoke not only the same language as the Croats (we once called it Serbo-Croatian) but also the same local dialect. Unlike the Croats, his religious heritage was Eastern Orthodox, but this attracted little notice in a secular urban milieu. He and the others were murdered because their lives challenged the notion of a pure Croatian identity.

The Ustasha town council did not learn about the murders until the next day, and its demand for an investigation was quashed by the Ustasha commissioner for Karlovac County. The victims’ families could have identified the five young men who had murdered their loved ones: they were followers of the little-known right-wing extremist Ante Pavelic, who had founded the Ustasha movement in 1930 in Italy, where he had been living in obscurity, along with several hundred other terrorists, under the protection of Mussolini before being empowered by Hitler. Pavelic and his cronies had seduced the killers of Vujicic with the glittering charms of power. A shrewd German intelligence officer knew the type: he reported to Berlin in July 1941 that “the Ustasha movement has attracted many new adherents and, since moral character was not an issue, the worst rabble can be found in its ranks.” One father sent his son from Karlovac to Switzerland so that he would not be tempted to fall in with such bad company.

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Did anyone authorize these young men to carry out the bloody deed? Historians have yet to find a written order for the Karlovac killings, but the absence of a paper trail is not unusual for outbursts of mass murder in fascist-controlled wartime Europe. In the fall of 1941, as German armies raced through Ukraine and Belarus, SS units in the rear began killing Jewish men, women and children. No written order from the leadership has been found to explain the slaughter, yet a common assumption about such killings—one Goldstein shares—is that violence against the same ethnic population at dozens of locales could not occur simultaneously without a centralized design and command.

To press the point home, Goldstein notes that Karlovac was not the only town in Croatia where prominent Serbs were disappearing. The Nazis had made Bosnia and Herzegovina part of the Croatian state, and on the evening of May 5, 1941, the Ustasha commissioner of western Bosnia ordered the murder of the Orthodox bishop of Banja Luka as well as a priest. Croats had previously rounded up hundreds of Serbs in three small towns in central Croatia (Gudovac, Glina and Blagaj), with special attention to teachers, lawyers, noncommissioned officers and Orthodox priests. They were shot before massive pits and their bodies covered with lime.

But in mid-May, the killing stopped. In one of the war’s little-noticed ironies, the Germans themselves expressed reservations about the violence, fearing it would destabilize a volatile territory, and worked to improve the conditions of Serb detainees; in Gudovac, they even arrested the Croat murderers. Many Croats were also horrified by reports of the killings, and doubts arose in the Ustasha leadership. In Karlovac, the town council was outraged. A minister in the new government in Zagreb hoped to use the fallout from the Vujicic murder to moderate the course set at the top by Ante Pavelic and his cutthroat deputy, Dido Kvaternik.

Pavelic modeled himself on Hitler. He was a teetotaler possessed of a grim charisma (though not especially skilled in moving crowds) and seemingly untiring in his devotion to the “nation,” which he claimed to embody. Like Hitler, he styled himself the “Leader” (Poglavnik) and had soldiers and civil servants swear an oath of loyalty to his person. Serious historians do not doubt that Hitler gave an order for the murder of Jews in the fall of 1941, and Goldstein does not doubt that Pavelic ordered the massacres of Serbs in the NDH that spring. But the power of the Poglavnik was derivative. In June 1941, Hitler received Pavelic for two hours at the Berghof and overruled skeptics in the German command. “If the Croatian state aspires to be truly stable,” he told Pavelic, “it will have to carry out a policy of ethnic intolerance for fifty years.”

The killing recommenced, and with such vengeful fury—men, women and children were burned alive in churches, drowned en masse or killed in a death camp at Jasenovac—that the Serbian population organized a massive response. Joining either ethnic fighting units (Chetniks) or the communist-led partisans, the Serbs began repelling attacks upon their villages and gradually liberating their territory from fascist rule. Violence begat violence: attacks on Croatian villages led to retaliations against unprotected Serb villages, and July through August 1941 became the bloodiest period of NDH rule as the Serbian rebellion spread, with particular strength in Bosnia, where the Nazis later formed Muslim units that fought the partisans and killed many Serbs.

This gruesome outcome was precisely what the Germans and some in the Croatian leadership had feared. But the racist fanatics were not deterred: by July 1941, Kvaternik already doubted that Germany would win the war. In the meantime, he said, the Ustasha would create facts on the ground that could not be nullified. Yet rather than ethnically cleansed territory, what the Ustasha left behind after its defeat in 1945 was poisoned memories. Hundreds of thousands died, mostly at the hands of other Yugoslavs—over 300,000 Serbs in Croatia and Bosnia, but also some 200,000 Croats and 75,000 Muslims. Unlike Poland or Czechoslovakia, however, Yugoslavia remained a patchwork of ethnicities after the war.

The fratricide of 1941–45 was not publicly discussed in postwar Yugoslavia. Tito and his comrades portrayed the war as a struggle of the “people” against fascism. But behind closed doors, each ethnic group remembered its own version of wartime violence. Croats said the Ustasha killings were responses to Serbian rebellion; Serbs knew that Croatian rule had meant genocide, and when communist control deteriorated in the 1990s, they mobilized to oppose an independent Croatian state that called itself democratic. The Croatian state’s leader, Franjo Tudjman, was a historian who had made a career in Tito’s Yugoslavia by claiming that the crimes of the Ustasha had been exaggerated.

The ferocity of Yugoslavia’s breakup was unthinkable without this prehistory; it also shaped the Muslim-Serb conflict in Bosnia, where Serbs likened Muslim Slavs to the Ottoman Turks who, in popular lore, had suppressed them for five centuries. But the proximate memory triggered, again, was 1941, when Muslims wearing the uniforms of the Croatian Ustasha or German-sponsored Bosnian SS had killed Serbs.

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How much complicity from a local population is required for genocide to occur? The Nazis sought and found collaborators, but given the lethal power of small numbers of soldiers armed with modern weapons, the active cooperation of locals in the mass murders of World War II wasn’t essential. We know that approximately 3,000 SS troops in mobile killing units were responsible for the deaths of close to 1 million Jews in Polish, Baltic and Soviet territories in 1941–42. The executions often took place in forests beyond the gaze of locals. Likewise, at the death camps, thousands murdered millions.

At a glance, the Croatian case seems similar: small groups from the Ustasha began killing hundreds, then thousands, of Serbs in the spring of 1941. Yet the genocide in Croatia was radically different. Whereas the Holocaust that the German armed forces perpetrated upon Polish, Baltic and Ukrainian Jews arose from years of rhetorical and ideological fervor stoked by a Nazi Party that was deeply rooted in German society, in 1941 the Ustasha had been in power for only a couple of days before the killing of Serbs commenced, and its connections to the local population were tenuous to nonexistent. The violence seemed to emerge from a historical vacuum—and rather than attract new supporters, the gruesome killings tended to repulse the local population, sending many Croats into the arms of the communist partisans. (The numbers grew late in the war as the front closed in upon southeast Europe.) In July 1941, a clear-eyed German captain noted the basic facts: “Virtually nothing was left of the enthusiasm of the Croatian people that greeted the arrival of our army,” he wrote; “deep distrust of Germany reigns in this country because it is supporting a regime that has no right to exist in either a moral or political sense.” In the recollections by Croats written after the war, “This was not the independent Croatia we imagined” is a common refrain.

If even the German command and some Croatian fascists opposed the killing, why did it happen? When the view is widened to include Hitler’s Europe, the consequential nature of events in Croatia startles even more. How did adventurers like Pavelic and his friends happen to acquire such power? Historians have a word for events hinging on the decisions of a few identifiable people like the Ustasha leaders, who lift themselves above the stream of history and impose their will on it, directing a new course. The word is “contingent.” Few historically significant events were as contingent as the genocide in Croatia in 1941.

One possible explanation is that the atrocities in Croatia were part of a German plan to control the continent: the first conquest was Austria in 1938, followed by Czechoslovakia and Poland in 1939, and then France, Belgium and the Netherlands a year later. In 1941, subjugation was the fate of Yugoslavia and the Soviet Union. This view is misguided. Until a few weeks before it bombed Belgrade in 1941, Germany had no intention of destroying Yugoslavia, let alone creating an “independent Croatia.” Hitler admitted this to Pavelic at the Berghof: originally he regarded Yugoslavia as part of the Italian sphere of influence, but “recent history” had made him the “unintentional instrument” of Croatia’s liberation. What he meant is that his ally Mussolini had attacked Greece without prior consultation in October 1940, and things did not go as planned. Italian forces were thrust into Albania, and the German command worried that Britain might move to control the eastern Mediterranean and perhaps the Balkan peninsula. That, in turn, could have imperiled the German southern flank in the attack on the Soviet Union that Hitler had planned for the spring of 1941.

Hitler therefore pressured Royal Yugoslavia to join the “Anti-Comintern Pact,” a military alliance that Hungary, Romania and Bulgaria had entered into during the previous months. At talks in Vienna, Yugoslav diplomats drove a hard bargain, securing an agreement that the country would not contribute troops to the German war effort and that no German troops would cross Yugoslav territory on their way to subdue Greece.

Yet circumstances intervened once more: on March 27, 1941, a handful of Serbian air force officers, incensed at the notion of any agreement with Germany, staged a coup and installed a more nationalistic government under King Alexander’s son Peter, not yet 18 years old. Crowds gathered in Belgrade to celebrate. But the plotters were also practical: among the first things they did was assure Germany that they would honor the pact. Even so, Hitler could not forgive this defiance and ordered the destruction of Yugoslavia, commencing with a merciless air attack on April 6.

Americans generally think that Western forces won the war in Europe by liberating Rome, landing at Normandy and bombing German cities. In fact, the turning point came in the Soviet lands that Hitler wanted to colonize, especially in the epic battles in the east at Stalingrad and Kursk, where Hitler lost his war. As it happens, a few rebellious officers in Belgrade had given the Soviets a chance to win. Because of their coup, Hitler had to postpone the invasion of Russia from April to June 1941, and his troops had yet to reach Moscow when the mercury fell below –30°C. Serbian royalists, all of them staunch anticommunists, had unwittingly given the motherland of socialism time to recover and, ultimately, to push the Germans back to Berlin. In a sense, Yugoslavia—the land Hitler had no intention to destroy—destroyed him.

As he confessed to Pavelic, Hitler had spent little time pondering the future of Croatia before the Belgrade coup. His first instinct was to offer it to Hungary (since the twelfth century, Croatia had been attached to the Hungarian crown). Mussolini had other ideas. Although Pavelic had been living under Il Duce’s protection since 1930, only now did the two men have their first meeting. By that point, the Croat spoke fluent Italian. Mussolini offered to support Croatian independence in exchange for territory in Dalmatia (historically Venetian but ethnically Croatian).

German leaders did not want a fascist regime, but one that would keep the peace and respect German interests. They sent an SS officer, Edmund Veesenmayer, to Zagreb on April 1 to offer Croatian peasant leader Vladko Macek the post of prime minister in an independent state; only when Macek refused did the Germans grudgingly agree to place power in the hands of the Ustasha. The party was being taken out of the mothballs, Goebbels said (“Wir werden sie bei Bedarf aus der Mottenkiste holen”). Yet between the activation—in Italian uniform—of 360 Ustasha members in late March and the founding of the NDH on April 10, there was no time to plan a coordinated set of policies. In this vacuum, the terrorist émigrés launched their “revolution” within days of returning to Croatian soil. According to Goldstein, in one place only—Bjelovar—did the violence against the Serbs arise from local sources.

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Nationalists think the nations they serve are eternal and necessary, entities created by God or some other transcendent power to effect its will in history. The reality is that nationalists themselves create nations and “invent” their traditions. Eastern Central Europe is a case in point: nothing about the nation-states that emerged from the ruins of the Habsburg or Ottoman empires after 1918 was natural—in each case, self-appointed patriots, many of them professors, had determined the standard languages, histories and boundaries of the nation, along with the idea that “their” nation was eternal and necessary. The Ustasha seems a radical case of this more general truth: in a few weeks in 1941, these few dozen right-wing nationalists—with their extreme ideas of what it was to be Croatian, mixed with heavy doses of violence—“invented” a tradition of Serb-Croat antagonism that has persisted to our day.

It would be wrong to say that the new “tradition” lacked local origins: after all, genocide did not break out everywhere the Germans established puppet regimes. In Croatia, the perpetrators may have been few, but they came from all walks of life, and no matter how extreme the Ustasha’s ideas, powerful Croats from all quarters—the Catholic Church, established parties, newspapers—called upon citizens to honor the new regime. Within weeks, an estimated 100,000 Croats had joined the ruling party. After the killing sprees, many endorsed the fictions that the Ustasha had concocted to justify its own crimes: that the abductions had been a response to a Serbian rebellion against the “Croatian state,” and that the Ustasha had simply “restored order.”

Slavko Goldstein wrote 1941 after finding such justifications in the history texts his grandchildren were reading in Croatian public schools. As both a witness and an eloquent professional historian, he mixes personal memory with the evidence drawn from court testimony and the Croatian press to show that the Serbian rebellion happened months after the initial violence ordered by Pavelic. Contrary to the idea—influential in the Clinton administration—of “ancient hatreds” spurring violence in the Yugoslavia of the 1940s and 1990s, there is little proof in the history of Croat-Serb relations of genocidal tendencies. Ustasha leaders may have complained about “centuries” of Serbian oppression, but the Serb-dominated Yugoslav administration had ruled in the region only since 1918. Before that, Serbs and Croats lived under Habsburg rule in Croatia and cooperated to blunt its repressive edges. It was to avoid continued Austrian or Hungarian (or Italian) domination after the Habsburgs’ rule collapsed in the fall of 1918 that Croatia’s political leadership petitioned the Serb king to join the new state, which we call Yugoslavia but was officially known until 1929 as the Kingdom of Serbs, Croats and Slovenes. The “oppression” of Croats under this hapless regime was such that Croatian economic and cultural life flourished throughout the interwar period.

The impetus for the genocide of 1941 lay not in tangible sources of discord, such as inequalities in economic or political power. More than any mass killing in twentieth-century Europe, the violence that erupted in Croatia was ideological in origin, deriving from native strands of thought about an ideal Croatian state and how Serbs theoretically constituted a problem for it. Though extreme, Pavelic emerged from a school of Croatian nationalism that had been formed generations earlier, some of whose adherents (such as Pavelic’s followers) make appearances in Goldstein’s account.

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The great contribution of the young historian Nevenko Bartulin is to connect this earlier history to the Ustasha without making 1941 seem a necessary outcome. In The Racial Idea in the Independent State of Croatia, he begins the story in the early nineteenth century, with the men and women who began imagining the East European nation-states that emerged a century later. They called themselves patriots, but their work was revolutionary, questioning the rule of states based on the monarchical principle and, in a broader sense, ushering into European history new ideas about human solidarity that are now grouped under the banner of ethnic nationhood. Impressed and humiliated by the power of the French nation (which occupied and controlled much of Europe from the 1790s to Napoleon’s defeat), intellectuals east of the Rhine wanted to make great historic actors of their own nations. Yet what exactly were those nations? At the time, there was no Italian or German national state, but rather hundreds of tiny principalities and other sovereign entities dotting the Italian peninsula and the lands stretching northward from the Alps to the North and Baltic seas. Further east was an imperial glacis under Habsburg, Ottoman and Romanov rule. Who knew what peoples might slumber beneath its surface?

To answer that question, Central and Eastern European intellectuals turned to the German philosopher Johann Gottfried von Herder, who wrote that a nation was not a state but rather a people united by culture and a common history—and the soul of a people was its language. Yet with that answer, the difficulties only began. The German lands featured dozens of mutually unintelligible dialects. Which was the region’s native language? The conundrum was repeated in Italy with its innumerable local variants, but greatly multiplied in Slavic Eastern Europe, with an unending array of similar yet different ways of speaking. Were Slavic tongues a series of dialects of one language, or did they represent many languages?

The linguistic similarities startled and intrigued Slovak and Czech intellectuals who traveled throughout Habsburg, Ottoman and Romanov lands in these years; because Slavic speakers have 40 percent of their vocabulary in common, they could make themselves understood in Belgrade, Kiev, Moscow and Warsaw. We now identify three great families of Slavic languages: West, East and South, within which the similarities are even greater. Yet in the early nineteenth century, basic philological research had yet to be done and people were unsure whether there was a Czech language, or whether Czech was a Bohemian variant of Czecho-Moravian-Silesian-Slovak or perhaps some other language spoken by even more people. The thrilling temptation for members of tiny peoples was to imagine that they were part of a greater language and history.

Amid this confusion and excitement, Ljudevit Gaj, a poet and linguist born near Zagreb in 1809 to German parents, preached that the South Slavs constituted one great people, whom he called Illyrians. His gospel was linguistic analysis. People from Slovenia down to Bulgaria, and from the Drava River across to the Adriatic, could understand each other almost perfectly without a translator. They spoke the language we called Serbo-Croatian. There are variations, but they are less severe than among the dialects of Italian or German.

Here is the vital point for all that followed: to include as many people as possible in this slumbering nation of Illyrians, down into Bosnia and Serbia and perhaps Bulgaria, this one man decided to use in his newspaper a variant of Serbo-Croatian spoken by most Croats and nearly all Serbs. By doing so, he omitted variants spoken on the Dalmation coast and in Zagreb, which had an important literary heritage. Gaj was charismatic and popular, but he never had more than a few hundred disciples. Still, an idea was born that South Slavs were a nation and should have a state; out of Illyrianism grew Yugoslavism, originally a Croat idea involving Croatian self-sacrifice (of the major literary language) for the sake of a larger community that existed nowhere but in the thought of a few dozen intellectuals.

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During these years, Serbian elites—who had finally wrested a semi-independent state from the Ottomans in 1815—ignored the Yugoslav idea, as did the overwhelming majority of Croats, who were not literate. As the decades passed and Habsburg rule continued, Illyrianism increasingly appeared a harmful distraction to Croatian intellectuals, who defended Croat traditions of self-rule dating back to the Middle Ages, when the Croatian nobility had joined Hungary. The most important voice belonged to Ante Starcevic, who founded the Croatian Party of Rights in 1861: by “rights,” he meant the rights of the Croatian lands, anchored not in fanciful ideas about language but in “liberties” once secured by the medieval nobility, such as directing internal administration, meeting in their own Parliament and attending the coronation of Hungarian kings (who were also Croatian kings).

Bartulin explains that Starcevic was the first Croatian politician to “define a modern Croatian national consciousness outside of a pan-Slavic or Yugoslav framework,” and the first to call for an independent Croatian state. The pressures grew after 1867, when the Habsburgs cut a deal giving the Hungarian elite control over the ethnically diverse Hungarian kingdom, including most of Croatia. (Now the Habsburg Empire would also be known as Austria-Hungary.) From that moment until 1918, the Hungarian government suppressed all non-Magyar cultural institutions in its territory and tried to make speakers of Slovak, Romanian and Serbo-Croatian into Hungarians.

As an opponent of South “Slavic” nationhood, Starcevic fiercely opposed all ideas of Slavic unity. According to the original Latin, Slav meant “slave,” an indolent barbarism, a threat to European civilization. The prime example of such “inferior” humans was Serbs, whom Starcevic called, in his proto-racial idiom, Slavoserbs, Orthodox slaves to other Slavs. They did not rise to the level of a people, but were rather a nomadic breed of heterogeneous origin, bereft of spiritual values and with little or no concept of land ownership and thus no concept of human dignity, or love for the home and law. They had served various rulers and even assimilated into different cultures, corrupting them with bad blood.

If the Serbs were descended from slaves, Croats were the progeny of fighters who had mastered the land. But Starcevic was not a consistent racist who thought characteristics were passed on immutably. Under Turkish rule, he wrote, some “captive spirits” (Slavoserbs) settled land and thereby lost their immoral substance and mixed with Croats. At the same time, he spoke of “impure blood” and “impure people” unable to create constitutional order, which had to be removed in order to create a harmonious society.

Starcevic was responding not only to increasing Hungarian oppression, but also to the emergence of Serbian nationalism in the growing and self-confident Serb principality (a kingdom from 1882) across the border. There, a competing view about nationhood arose from the work of Serbian linguist Vuk Karadzic: all speakers of the main form of Serbo-Croatian—the same one Gaj wanted to make the basis for Illyrian—were in fact “Serbs” and should be included in the Serbs’ national state. For him, most Croats were Serbs who had converted to Catholicism. That understanding became a policy of the Serbian state, which planned to expand ultimately to all lands where “Serbs” lived.

The case of Starcevic offers a caveat to Benedict Anderson’s idea that nations are “imagined communities.” The precise form a nation takes may indeed be imagined, but whether it emerges in the first place depends upon historical factors that are not directly controlled by human will. Bartulin writes that Starcevic appealed to something more substantial than “Yugoslavism”—namely the actual history of a people living on a bounded territory (the kingdom of Croatia), with (partly fictionalized) memories of the deep past (for example, of heroic Croatian kings) and shared experiences of Habsburg (as opposed to Ottoman) rule. A new layer of shared history was added in 1918 when thousands of Serbian soldiers and officials entered Zagreb in the process of establishing Yugoslav statehood; although they spoke the same language, Croats saw them, with their very different political traditions, as aliens.

Soon an ethnicized vocabulary emerged to explain the inefficiency and corruption of the mostly Serb bureaucracy in the new state. Even one of the Croatian architects of Yugoslavia, former Split mayor Ante Trumbic, partook of it. In 1935, he explained in an interview that it was pointless “to compare…the Croats, the Slovenes, the Dalmatians, whom centuries of artistic, moral and intellectual communion with Austria, Italy and Hungary have made pure occidentals, with these half-civilized Serbs, the Balkan hybrids of Slavs and Turks. They are barbarians, even their chiefs, whose occidentalism goes no further than their phraseology and the cut of their clothes.”

Perhaps nowhere else in Europe did a nationality come to feel as embattled as in Croatia, with so many forces conspiring to deny indigenous claims to nationhood—beginning with Croatia’s first nationalists, who had wanted to disappear into a larger Yugoslav whole. There were also the Magyars, who wanted all Croats to be Magyar; the Croatian Serbs, who opposed a Croatian national state; and the Serbs across the border in Serbia, who thought Croats were Serbs (even when they called them Yugoslavs). In addition, the Croatian lands had been divided before World War I, mostly under Hungarian (Croatia-Slavonia) rule, but some under German-Austrian (Dalmatia). Not only Hungarians but Germans refused to recognize Croatia’s right to nationhood (Friedrich Engels called it an “un-historic nation,” meaning it was destined to be absorbed into other peoples). Italians thought the Dalmatian coastline belonged to them (its population supposedly consisting of Slavic-speaking Italians), and Italian fascism first reared its head when Gabriele D’Annunzio seized Rijeka (Fiume) in 1919. There were also the Croats of Bosnia-Herzegovina (Ante Pavelic was born there). Beyond these political divisions, Croats spoke three major dialects—and most of them used one much closer to the dialect spoken by Serbs than that of Croats in Zagreb or on the Dalmatian coast.

The one institution that unified Croats above all these divisions, and in clear distinction to Serbs, was not even national, but rather famously multinational. Like the Habsburgs, the Roman Catholic Church cared little about Croats; for Rome, nationalism was a modern heresy. Starcevic’s bitterest opponent in the late nineteenth century was a Catholic bishop named Strossmayer, a fervent Croatian patriot, but at the same time a Christian who favored cooperation and compromise. After the decline of these two old men of the Croatian cause, in the early years of the twentieth century, a more extreme version of Starcevic’s views emerged among the followers of Josip Frank and his party of “pure right”; yet as the franchise expanded, his views proved much less popular than those of the Croatian Peasant Party under Stjepan Radic, a democrat who became Croatia’s true leader in the new Yugoslav state.

Yet for nationalists, the creation of that state froze the Croatian problem into its most frustrating form yet: it robbed them of a language for lamenting their failure to achieve statehood. After all, Yugoslavia was “their” state. Stjepan Radic told his daughter in 1919 that his “soul ached” when he saw the Serbs doing the same thing to Croats in Yugoslavia that Hungarians had done to Slovaks in Austria-Hungary (he was exaggerating); but “our predicament is that we are ‘brothers,’ we are ‘one,’ so that you cannot complain about this.” Radic was the one figure in Croatian public life who opposed the decision of Croat elites to join Yugoslavia in December 1918, and he warned the latter-day Illyrianists that they were like “drunk geese going into the fog.” He led his party in passive resistance until 1928, when a Montenegrin deputy shot and mortally wounded him on the floor of Parliament.

King Alexander offered autonomy to Radic’s successor, Vladko Macek, but he demurred, fearing Croatia was too weak to stand on its own. In 1929, the king dissolved Parliament and ruled as a dictator until his assassination five years later by a Macedonian in the employ of Italy and the Ustasha. The Ustasha had a vision of its own: it took existing grievances and proposed (in the terms of ethnic nationalism) a consistent and logical program. What linked Croats was not culture, politics, language or religion, but race. In contrast to other fascists, the Ustasha was not a party of imitators. Before he escaped to Italy, Ante Pavelic was a secretary of the Croatian Party of Rights (with 0.1 percent of the votes in 1925), and he refined the proto-racism of Starcevic’s thought into a coherent ideology: Croats were a superior people; real boundaries separated them from other peoples; yet the inferiority of “Slavoserbs” made it impossible for them to see these truths. Starcevic had also supplied the anticlericalism that permitted overtures to Muslims in Bosnia as supposed descendants of the purest Croatian stock, having sacrificed their religion after Ottoman conquest to retain their lordship. Starcevic admired Ottoman rule, which he viewed as more tolerant, and because it formed a bulwark against corrupting influences of the West.

Ustasha leaders drew upon the work of Croatian anthropologists to cultivate these ideas, arguing that Croats constituted a non-Slavic group. They were a unique Indo-European people sharing the physical and mental traits of the main European racial types (Nordic, Dinaric, Alpine, Mediterranean and East Baltic), while the best Croats bore traits of the “exceptional” Dinaric and Nordic races. Croatian racists outfitted these notions with German-dominated anthropological scholarship, with all the period’s ideas about cranial shape, eye color and the like. Pavelic believed that his region’s people bore the characteristics of the “tall, organized, martial and authentic Croatian population of slightly darker hair.” These indices in turn “proved” the dominant presence among Croats of Germanic-Gothic blood: they, too, were Aryans. Yet whereas no German anthropologist needed to demonstrate that there was such a thing as the German Volk, the Ustasha, writes Bartulin, “used racial anthropology mainly in order to prove the very existence of a separate Croat narod [nation] and dispel the theory of a united ethnolinguistically Yugoslav people.”

The recourse to race seemed urgent because other Europeans saw Croats not as state builders but rather, with the multi-regional Italian precursor in mind, as a regional group destined to disappear into the larger whole of Yugoslavia after the lead of Serbia. The common use of the word “Yugoslavs” in the period to denote Croats (among others) explains why the Ustasha wasted no time showing it was wrong. By abducting assimilated Serbs, young fascists spearheaded the entry of the Croatian nation onto the historical stage, creating “facts” that no one could ignore: a people of one blood that was part of no other, but (like all ethnic nations) fully authentic and derivative of nothing else, able to stand on its own.

What they succeeded in doing was turning the spotlight on themselves as Europe’s most insecure racists. Their nativist turn was a patent farce: Ustasha leaders often spoke better Italian than Croatian; were propped up by German power, wore German insignias, fought in a German war; and had ceded the Dalmatian coast to Italy in return for “independence.” They were deeply anti-Bolshevik, but did more than anyone to bring socialist revolution to Yugoslav territory. Without the thousands killed by the Ustasha in its “national revolution,” Tito’s partisans could never have recruited the hundreds of thousands (including many Croats) who brought them to power.

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Since its publication in Croatia in 2007, Goldstein’s memoir has gone through multiple printings and garnered high praise there. Bartulin’s book has appeared only in English. In 2012, the Review of Croatian History, the flagship journal in Zagreb, gave a senior historian over sixty pages to excoriate a single article about race and culture in Croatia by this young historian. (Bartulin taught at Split for a brief time but has since returned to his native Australia.) The crimes that Goldstein details are undeniable; but Bartulin, by linking them to Ante Starcevic, often called the “father of the Croatian nation,” has touched a nerve. Mainstream Croatian historiography considers the Ustasha to have been a pragmatic effort at securing Croatian statehood. To call it a racist regime with roots in Croatia’s earlier national tradition, which was Catholic and therefore supposedly non-racist, is to mainstream Croatian historians unthinkable. Yet Bartulin is anything but one-sided or simplistic. Yugoslavia was immeasurably more tolerant than the Independent State of Croatia, he writes, but it too suffered from the original sin of ethnic nationalism. It was, as Kosovar Albanians or Banat Hungarians will remind you, a “Slavic” state. In 1945, a Yugoslav military court condemned to death the 78-year-old Croatian priest Kerubin Segvic for claiming that Croats were of non-Slavic origin.

The fortuitous appearance of Goldstein’s and Bartulin’s books in the space of a few months—the former an eloquent memoir and analysis by one of Croatia’s respected senior historians, the latter a brilliant and original first academic work by a student of European racism—allows us to recognize a deeper tragedy in the Yugoslav wars of the 1990s, beyond the hundreds of thousands of lives lost. With the death of Yugoslavia came not only the fall of a multiethnic state, but the apparent failure of the idea of co-existence in a European nation-state. These books show that this failure was not inevitable: if we examine the chain of causation, tugging lightly on numerous links—especially the year 1941—it eventually comes apart in our hands. The genocide of that year was not foreordained by earlier history. If most Germans never voted for Hitler (let alone his war), no Croats freely voted for the Ustasha, which had several hundred active members in the year it placed history on a different course. But the track was already well worn, evolving as it did from past aspirations to create an ethnically pure nation-state. The Croatian people had not desired the crimes of the Ustasha, but without those crimes, the mostly homogeneous Croatia of our day would be unthinkable. Without 1941, in short, we cannot imagine the ethnic conflict of the 1990s—first the ethnic cleansing of Croats by Serbs fearing a reprise of the earlier genocide, and then the cleansing in 1995 during Operation Tempest, when between 150,000 and 300,000 Serbs fled before advancing Croatian forces. (The US Secretary of State Warren Christopher welcomed this development, which occurred within weeks of the massacre in Srebrenica, because it gave rise to a “new strategic situation that may turn out to be to our advantage.”)

Must this pattern be repeated elsewhere? Can a European nation east of the Rhine be organized on a principle other than ethnicity—that is, de facto racism? That question is being tested in Ukraine. The journalist Anne Applebaum wrote recently that without “nationalism” to bind its people together, Ukraine cannot survive. But what sort of nationalism? The Harvard historian Roman Szporluk has written of the “crucial need for Ukrainians to uphold the principle that Ukraine really is a multiethnic political nation…a ‘jurisdiction,’ and not an ethno-linguistic entity.” If this vision is realized, it will break with a tradition that originated with Herder and Ljudevit Gaj, when people were told that they could be their true selves only in union with people of the same blood and language—a union all too often consecrated with the blood of others.