In October 1699 a ship called the Liverpool Merchant set sail for Africa, proceeding thence to Barbados with a cargo of 220 slaves. Among the ship’s owners was Sir Thomas Johnson, who that same year joined with a movement of slave traders to establish Liverpool as an independent parish. And so the port city in what was then still part of Lancashire was initiated into the Triangular Trade. Between 1700 and 1807, about 1.5 million African slaves were transported across the Atlantic on ships that had set sail from Liverpool. Controlling 40 percent of the European slave trade and a similar proportion of the world’s trade in general, Liverpool rivaled London in terms of wealth.

The grandiose architectural offspring of the city’s former shipping might are still visible on its waterfront. One of the more recent is the Cunard Building, completed in 1917 in ornate Italian Renaissance style. The Canadian-born Samuel Cunard had parlayed a contract for transatlantic mail shipment into the world’s most prestigious passenger cruise line; he represents an era in which Liverpool’s maritime industry had sloughed off the shame of the slave trade. His great-granddaughter Nancy Cunard was an energetic promoter of literary and artistic Modernism who also edited the 1934 collection Negro: An Anthology, a landmark of the Harlem Renaissance that has been called "the first publication to voice freely perspectives and ideologies from diaspora blacks and Africans."

If there is any doubt that coming to terms with this history remains painful, consider what happened in 2006 when the Liverpool city council decided that street names linked to the slave trade should be changed to honor abolitionists. When it emerged that Penny Lane, the subject of the famous Beatles song, was named for an eighteenth-century owner of slave ships who testified in favor of the slave trade before Parliament, and that it therefore would be one of those renamed, there were howls of rage. "Few songs are lodged in the national psyche like Penny Lane," the Guardian conceded. "Penny Lane should keep its name, but its fame should be used to make people aware of its shameful history." (In a letter to the editor one of the paper’s Australian readers took sweet reason to even greater lengths: "The solution to the Penny Lane problem is obvious: commemorate the song instead and rename it Penny Lane Lane.") The street remains Penny Lane, and tourists still go there looking for the shelter in the middle of a roundabout.

Tate Liverpool is located in a considerably less flamboyant structure than the Cunard Building, a former warehouse in the Albert Dock, but given the city’s history it is hard to think of a more apt setting for its current exhibition, "Afro Modern: Journeys Through the Black Atlantic" (on view through April 25). As the subtitle discloses, the exhibition takes its inspiration from British sociologist Paul Gilroy’s groundbreaking 1993 book, The Black Atlantic: Modernity and Double Consciousness. Thanks to its international reach, Gilroy’s notion of the Black Atlantic offered one of the most suggestive distillations to date of an idea that was broadly articulated by Alain Locke nearly seventy years earlier, that "to be ‘Negro’ in the cultural sense" is "to be distinctively composite." It’s peculiar, then, that Gilroy is not among the contributors to the exhibition catalog. (Music and the written word, rather than the visual arts, have been Gilroy’s primary cultural sources, as reaffirmed by his provocative new book Darker Than Blue: On the Moral Economies of Black Atlantic Culture, with its more somber view of the cultural scene Gilroy evoked in 1993.) By the same token, as Courtney Martin points out in her contribution to the catalog, even before Gilroy, Robert Farris Thompson had written of a "black Atlantic visual tradition"–though Thompson is not a contributor either.

While it seems evident that the violent yet galvanizing conjuncture of European and African elements in, mostly, the Americas has produced a world-historical transformation of musical culture, and an unprecedented politics of liberation as well, its effects on visual art have been more difficult to measure. The profound effect that African tribal sculpture had on Matisse, Picasso and European and then international Modernism in general is well-known. But to what extent was this the beginning of a broader transformation, one with consequences not only for white European artists but for artists in Africa and in the African diaspora in Europe and the Americas? To what extent, that is, can we speak not simply of a Euro-American encounter with African art but of a mutually transformative encounter of European, African and diasporic cultures? These are the kinds of questions at stake in "Afro Modern," and while the exhibition can only begin to pose, not answer, them, the very fact that they are being asked is already a considerable achievement.

The exhibition’s first section, "Black Atlantic Avant-Gardes," juxtaposes works of very different sorts. Paintings, drawings and sculpture by Picasso, Brancusi, Léger and Karl Schmidt-Rottluff illustrate the astonished Western discovery of African art, as do Walker Evans’s photographs of tribal masks. There is also evidence of the social response to the increasing black presence in Europe: a print of Josephine Baker performing in her famous banana skirt; a caricature of an interracial couple dressed to the nines. (The drawing, in the collection of the National Portrait Gallery in London, is identified as "probably" Nancy Cunard and her lover, the black musician Henry Crowder; but according to Crowder’s biographer, Anthony Barnett, it is not them.)

This is already a very mixed bag. Picasso, most notably, was inspired by African art to foment a thoroughgoing revision of the very syntax of representation–a revision that the others, Brancusi perhaps most of all, seized on with relish for its potential to be subjected to their highly personal reinterpretations. Paul Colin’s lithe, stylish impression of La Baker has no such ambitions. Also in this section are works from the 1920s by white South American artists who employ Modernist stylization–the Brazilian Tarsila do Amaral had studied with Léger in Paris–and the awkward rhythms of folk art to observe the black cultures around them, and above all works by black artists of the Harlem Renaissance, who, to one degree or another, were productively reacting to both Modernist and African art. Naturally, these artists appreciated the latter with a "double consciousness," to borrow W.E.B. Du Bois’s famous phrase: as the heritage they were eager to reclaim and as a source of the Modernist syntax, which at least some of them viewed as the means to effect that reclamation or in any case as a stylistic badge of the contemporaneity of their artistic quest. Here I was particularly taken with two sculptures by Ronald Moody, a Jamaican-born British sculptor whose work I had not known before. His Midonz (1937) is a massive female head of carved elm that persuasively demonstrates that Modernist reduction could reveal a timeless serenity not unlike that of archaic Greek sculpture. Moody’s works were shown alongside those of his American colleagues at the Baltimore Museum of Art in 1939 in an exhibition of "Contemporary Negro Art," but his works in "Afro Modern" have a stylistic authority that the Americans’ lack.

The next stage in the evolution traced by the exhibition is titled "Black Orpheus: Negritude, Creolization, Natural Synthesis." The term "negritude" was coined, of course, by Aimé Césaire in the mid-’30s, but the period covered at the Tate is roughly the mid-’40s through the mid-’60s–essentially the era in which Europe’s former colonies in Africa were gaining independence and black consciousness was manifesting renewed élan. This was the beginning of what would later be called Afrocentric thinking. It’s at this juncture in the exhibition that modern African artists (rather than the anonymous makers of tribal artifacts) appear for the first time. By the same token, Maya Deren’s film Divine Horsemen: The Living Gods of Haiti, assembled after her death from footage shot in 1947-51, exemplifies a new turn in the white avant-garde’s involvement with "exotic" black cultures. It was no longer a matter of connoisseurial rummaging in Parisian flea markets but of a pilgrimage to the source, and a concomitantly heightened sense of the embeddedness of masks and other objects in ritual.

The "Natural Synthesis" of the section title refers to the ideas of Nigerian artist and theorist Uche Okeke, whose take on negritude emphasized contemporaneity and heterogeneity over tradition and authenticity. Cuban, Brazilian and American artists held similar goals, but as hopeful as such a synthesis of old and new African and European influences may sound, the results often seem strangely bloodless–something that could hardly be said of the succeeding section, "Dissident Identities: Radicalism, Resistance and Marginality," which features works reflecting the civil rights and black power movements of the ’60s. The polemics here hardly seem dated, and are not limited to black artists; Andy Warhol’s 1964 silkscreen print Birmingham Race Riot is right at home with Adrian Piper’s 1975 drawing I Embody Everything You Most Hate and Fear. But within this countercultural uproar, another theme begins to emerge in counterpoint to overtly racial concerns: gender politics. Art historian Judith Wilson is quoted to explain that Romare Bearden’s extraordinary collages–which have been looking more and more relevant again of late–"recuperate the black female body, wresting it from the clutches of white purveyors of erotic fantasies about exotic Others, and reposition it in relation to black vernacular culture." No doubt, but this still leaves open the issues of inequality within that culture.

A different view of the black female body emerges in a work by a woman artist–Piper’s Food for the Spirit (1971). This sequence of murky black-and-white images showing Piper photographing herself in a mirror evokes a self-confrontation that involves opacity more than clarity, unknowing as much as enlightenment. The artist/philosopher’s gaze, seemingly troubled and doubtful, is toward and for herself; she looks forward but not outward, and the viewer becomes marginal–not a voyeur, yet neither welcomed nor challenged. Her nakedness seems to speak less about sexuality or gender than of a reduced and isolated sense of self.

The exhibition’s last three sections, "Reconstructing the Middle Passage: Diaspora and Memory," "Exhibiting Bodies: Racism, Rationalism and Pseudo-Science" and "From Post-Modern to Post-Black: Appropriation, Black Humour and Double Negatives," bring the story of the Black Atlantic up to the present with works dating mostly from the past two decades. The multiplication of categories suggests that the present and immediate past are harder to encapsulate than previous eras–which is always the case–but also reminds us that the complexities of history, and the strategies for dealing with them, are essentially the same as forty years ago: mourning, protest and humor are still of the essence. In retrospect, "post-black"–a term coined by curator Thelma Golden of the Studio Museum in Harlem and artist Glenn Ligon–represents a depth and complexity of ambivalence that exceeds any merely double consciousness, and typically characterizes much of the strongest black art. That’s why I say Bearden is a central figure. It is hard not to have mixed feelings about his formally and semiotically dense and raw concatenations of imagery, and those mixed feelings amplify rather than dissipate the work’s appeal. His influence on an artist like Wangechi Mutu is most patent, but it’s not hard to find in many of the other relatively younger artists here (few are under 40), such as Ellen Gallagher, Kara Walker and Chris Ofili. The collage-based conflation of the pornographic and the sacred, suspending judgment, critique and satire, in Ofili’s The Holy Virgin Mary (1996)–the painting (now on view at Tate Britain in London) that caused such a foolish ruckus when the "Sensation" exhibition came to the Brooklyn Museum in 1999–is as raucously Beardenesque as you could want.

By contrast, Judith Wilson’s desire to offer a politically righteous alibi for Bearden’s unresolvable little pictorial desire machines seems like a turn away from the risk and exposure of the post-black position that was already implicitly his. To some extent, this is true of the exhibition as a whole. The downside of its laudable ambition is the need to thematize everything and to seek out what has already been thematized at the expense of what resists explication. In the "Afro Modern" catalog, the great Martinican writer Édouard Glissant explains in an interview that "a person has the right to be opaque," and this is because "a racist is someone who refuses what he doesn’t understand." Glissant’s insight is profound but painfully hard to act on. An exhibition like "Afro Modern" tends to refuse what is opaque. Another way to put it would be to remember Stuart Hall’s plea in an essay published in 1996: "I ask you to note how, within the black repertoire, style–which mainstream cultural critics often believe to be the mere husk, the wrapping, the sugar-coating on the pill–has become itself the subject of what is going on." What Glissant calls opacity is inseparable from what Hall calls style. The need to find clearly marked subject matter tends to deflect attention from the importance of style as such.

One way that this inattention manifests itself in the exhibition is through the near suppression of abstract art. Rubem Valentim’s paintings are didactic illustrations of how abstraction might absorb forms redolent of Afro-Brazilian culture but feel like a compromise more than a real synthesis. "Afro Modern" includes pieces by other artists who worked abstractly, such as Norman Lewis and Frank Bowling, but pieces in which abstract motifs are allegorically overlaid with more overt topical content. Their abstract works, not to mention those of artists like Alma Thomas, Beauford Delaney, Sam Gilliam, Martin Puryear, Leonardo Drew and Mark Bradford, are essential to any visual survey of the Black Atlantic. I also wonder about missing figures such as William H. Johnson, Robert Colescott (another of Léger’s students, by the way), Barkley Hendricks and Kerry James Marshall, whose works are far from abstract but which exemplify stylistic peaks that I felt as sore absences in this context. I mention American examples because that is the context I know best, but the examples could multiply internationally. Moreover, the focus on subject matter over style means that some artists are represented by weaker work than they should be. A prime example is Jacob Lawrence, here with an African street scene from 1964, which serves to illustrate the growing ties between black American artists and the mother continent at the time. But Lawrence’s greatest paintings are his early ones, from the late ’30s and early ’40s, and those are the ones that helped make a future for Black Atlantic style. Wifredo Lam is rightly presented in the catalog as the premier artist of negritude, but you’d never know it from the minor examples of his work in the exhibition. Likewise, from the single photograph exhibited here, the viewer has no way to understand what has made Isaac Julien such a significant artist and filmmaker over the past two decades; his idiosyncratic compound of extreme aestheticism and moral intensity cuts across all invidious dualisms.

Few artists today exemplify style–and its opacity–as acutely as Chris Ofili. His current retrospective at Tate Britain (through May 16) underlines the fearlessness it takes to let your work go that far. It’s also a good reminder of how in-your-face blatancy can be just as good a vehicle for opacity and style as ambiguity and nuance. Ofili knows it. As he tells interviewer Ekow Eshun in his solo catalog, "Sometimes though, I’m just blindingly obvious, an example being Afrodizzia. Like, bang, there it is. Afro head–celebration of Afrocentricity." You can be that obvious with style, of course, if you’ve got a lot more going on than just what you’re being so obvious about. Afrodizzia (Second version) belongs to the first phase of Ofili’s work, or anyway the earliest phase shown here, in which imagery is subsumed by pattern and the play of materials. Collaged to its surface are, indeed, a plethora of heads with Afro haircuts–dozens of them, maybe hundreds. You can never lose sight of them, not for a minute, but there is so much more going on in the painting: the collaged heads are just one layer in a dense commotion of optical, linguistic and tactile elements (including the famous varnished balls of elephant dung) that manage to create a coherent visual field only by the skin of their teeth. The thrill of the painting is that, miraculously, the elements do cohere.

Painted in the same year, The Holy Virgin Mary is part of the next phase of Ofili’s development. Figurative drawing–flat and posterlike but with great bravura and proffering a single, centralized, iconic image–rather than pattern dominates, and to a great extent visual coherence comes more easily. But in compensation, the paintings become more complex emotionally. Mixed feelings about women come to the fore. The Holy Virgin Mary could have been a simple illustration of the age-old virgin/whore dichotomy–except, where’s the dichotomy? Carnality and the spirit simply coexist, with no resolution of their potential contradictions, and none sought. By 1999 Ofili seems to have become interested in synthesizing his new figurative content with his earlier emphasis on abstract pattern. This doesn’t always succeed–The Upper Room (1999-2002), a chapel-like installation of thirteen paintings (on the model of Christ surrounded by the Twelve Apostles, but here substituted by rhesus macaques), is grandiose rather than raucous when it probably should have been both. But what’s intriguing about Ofili’s best paintings of this period–from Prince Amongst Thieves (1999) to Afro Sunrise (2002-03)–is how they start to feel like their own camouflage. Their visual density heightens one’s awareness that they contain more than one can easily make out, but it also suggests that density itself might be the main thing to see, to accept. There is much hidden in these paintings, and you always feel as though there’s something inside them that might be looking out at you, spying, as much as you’re looking at the paintings.

Then, between 2003 and 2006, comes a break from painting, though not from drawing. In 2005 Ofili moved from England to Port of Spain, Trinidad, a place where he had no roots, although his friend and fellow painter Peter Doig, who had spent his childhood there, had returned a few years earlier. There are curious parallels in the effect that moving to the island has had on the painters. Doig and Ofili paint very differently, but one thing their paintings have had in common is that they were built from the micro level up, their images like condensations of innumerable small marks, swarms of punctual sensations. Slowly, after Doig moved to Trinidad, his paintings began to clear out, to become broader and more open, and at the same time more mysterious. Something similar has happened with Ofili, but more suddenly. Starting in 2006, there is a sequence of close-valued, dark-blue paintings whose imagery, stylized in a way that recalls German Expressionism, can be very difficult to make out. Perhaps the most legible is Iscariot Blues (2006). Judas, the Gospel of Matthew tells us, ended his shame by hanging himself. Here the gaunt, naked body hangs broken-necked as he is serenaded, or so it seems, by a pair of musicians. It’s an eerie and terrible image that to some extent makes one grateful for the deeper opacity of some of the other blue paintings.

Other recent Ofili paintings use a wider range of hues with more contrast, but still with these expressionistic distortions of the figure. Not only has Ofili transformed his technique, and the surface quality of his paintings, but the nature of his drawn line has changed as well. Before it was rounded, voluptuous, seductive; now it is tense and elongated. Ofili speaks of "a very particular mystery" that he derives from the Trinidadian landscape, adding, "Essentially there’s a joy I feed off." And yet the paintings are not joyous, at least not in the way so many of his earlier, more insouciantly bad-boyish ones were. At best, perhaps, one can speak of an amor fati. There is something haunted in these paintings, a sense of fatality that was not there before. And with that, a sense of existential weight. The imagery in these paintings is not iconic, as in earlier works like The Holy Virgin Mary. Instead it conjures up narratives, though of unclear purport. There is a sense of hidden dramas, of fables with secrets. This affinity with the riddling quality of legend or parable recalls the art of Bob Thompson, the American painter of the ’60s–another of those figures who might have been worth including in "Afro Modern" but wasn’t. The paintings evoke, whether Ofili realizes it or not, a thought that Glissant has explained in this way: "The Africans in the New World–African-Americans, but also the Antilleans, Brazilians, etc.–escaped the abyss and carry within them the abyss’s dimensions." Ofili’s heritage is otherwise–his family having come to England from Nigeria in the 1960s, they are not part of the diaspora that endured the middle passage and slavery–yet in the Caribbean he seems to have glimpsed and been affected by the dimensions of that abyss.