A representation of the time when people of African descent in Mexico stood to lose their heritage in a culture that encouraged denial of their skin colour

Sometimes you have to look out to see in. An exhibition at the Smithsonian's Anacostia Community Museum about Africans in Mexico is not about race in America, or African American identity or what it means to be black in the United States.
But by focusing on African existence in Mexico, it reveals far more universal wisdom about race and identity than so much of the often rancorous "discussion" of the subject on this side of the border.
The African Presence in Mexico: From Yanga to the Present documents the arrival, disappearance and reappearance of African identity in Mexico over the past five centuries, using art from the colonial era, photographs and contemporary crafts, sculpture and imagery.
Beginning in the 16th century, when enslaved Africans were brought on the first missions of discovery and conquest, it explores how the Spanish articulated race into categories, including mulatto (half Spanish, half African), mestizo (half Spanish, half native) and 14 other permutations.
After the war of independence from Spain from 1810 to 1821, these categories were suppressed as an unwanted vestige of Spanish colonial rule.
The shorthand for ethnic identity recognised skin colour, with fairer tones more privileged. Distinctions were still made between native and Spanish-descended identity but African descent got lost in the mix. The exhibit's most striking images show what was hiding in plain sight.
As Mexico created a new melting-pot identity that assimilated yet denied blackness, artists documented the racial diversity that was officially disappearing. The three figures in a lithograph by Carlos Nebel, a German artist who travelled in Mexico from 1829 to 1834, all "read" black, at least to an outsider.
And so the exhibition becomes a game: Find the African identity. This puts the viewer in the strange, and sometimes uncomfortable, position of looking for blackness in images of people who would not necessarily consider their African descent of much importance but who would, in this country, be labelled "black".
The exhibition seeks to document a suppression of identity that was, at first, perhaps progressive but became over time a collective denial of the contributions of African-descended people.
By the time you reach the Mexican Revolution (1910-1920), the popular conception of a new Mexican identity had marginalised the African presence.
This creation of a "brown" identity was an ambiguous project. Having African features was not the automatic ticket to poverty and discrimination that it was in most of the United States. But there was a cost: the loss of heritage, history and identity.
The exhibition divides into roughly three chapters, beginning with the Spanish years, followed by the 19th- and 20th-century suppression of African identity and closing with art that explores the recent emergence of a newly configured Afro-Mexican identity.
After sorting through photographs made in Guanajuato, curator Cesareo Moreno of the National Museum of Mexican Art assembled a wall of faces, most obviously black. But even Moreno's uncle, who lives near where these standard portraits were made by a photography studio in the late 19th and early 20th centuries, said no black people were near the town.
When researching the exhibition, Moreno says, he was shocked to rediscover the blackness in a striking photograph made during the Mexican Revolution: of a dark-haired woman with full lips. Take her out of her Mexican clothes and put her in the segregated South and she would have been sent to the back of the bus.
But it wasn't until Moreno looked for it that he found her blackness: "Once you start seeing it, it is everywhere."
But would this young woman have defined herself as black? And if she didn't, who are we to "rediscover" it in her?
That leads to the powerful ambiguity of the exhibition's third chapter, devoted to artists who have focused on the newly emerging idea of an Afro-Mexican identity.
The black photographer Tony Gleaton has worked extensively in Mexican regions with large African-descended populations, creating haunting images of dark-skinned people. But he wasn't perceived as "black" when he travelled in Mexico.
As a journal Gleaton kept in 1988 during his time in Mexico points out, he was also projecting his own ideas about race: "The photographs that I create are as much an effort to define my own life, with its heritage encompassing Africa and Europe, as an endeavour to throw open the discourse on the broader aspects of ‘mestizaje', the ‘assimilation' of Asians, Africans and Europeans with indigenous Americans."
There is an essential difference between finding something and forging something and the exhibition's third chapter is about the latter.
If blackness seems to peer out of the silence of old images from earlier centuries, it is presented more boldly and sometimes stridently in art made since the slow reawakening of Afro-Mexican identity during the past few decades.
The most provocative of the works is a painting commissioned for the exhibition from Arizona painter Alfred Quiroz.
His 2005 Kozmic Race mobilises just about every stereotype in the Mexican and American catalogue, from a hook-nosed and glowering conquistador to an African with chains on his arm and a bone through his nose, to a native Mexican, apparently holding human hearts as if fresh from some grisly Aztec ritual. It also references a 1938 lynching in Florida.
Quiroz's painting makes one wish that "Afro-Mexican" identity could be studied and observed as if an objective fact. But there is no observing it without importing American and other ideas about race.
And just as you are about to dismiss Quiroz's painting, you realise art has always been used to forge ethnic and racial identities. His painting is a part of a centuries-old project.
But is it a good project? Does it need to continue? Is a forgotten or suppressed identity best left dormant? Or is there a way to awaken difference without division, identity without animosity?
Like all good exhibitions, The African Presence in Mexico raises more questions than it answers. But it goes beyond the merely good by raising provocative and painful questions in a forthright way alien to all too many exhibitions about race today.
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