WHAT WE CAN LEARN FROM THE RISE AND FALL OF ‘POLITICAL BLACKNESS’. Before “people of color” and BIPOC, Britain had its own inclusive concept for nonwhite people.

By Kwame Anthony Appiah

How Black is Kamala Harris? That the question gets posed speaks to the ill-defined contours of an ill-defined concept. Ms. Harris, the daughter of an Indian-born mother and a Jamaican-born father, has been called in the media “half Black,” “biracial,” “mixed race” and “Blasian.” In online posts, people have ventured that she’s “partly Black” or — for having attended Howard University, a historically Black school — an “honorary full Black.” Others persist in asking whether she’s “Black enough.”

The old British concept of “political Blackness,” the heyday of which stretched from the late 1970s to the early 1990s, would make nonsense of such questions in a very immediate way: Ms. Harris’s mother, by this definition, is just as Black as her father. For proponents of political Blackness, “Black” was an umbrella term that encompassed minorities with family origins in Asia and the Middle East as well as in Africa and its diaspora. That’s not to say it was the sturdiest of umbrellas: It was never uncontested. Yet it may have lessons for us today.

In Britain, anyway, its legacy remains legible. Three years ago, in a public-awareness campaign designed to increase voter turnout among British minorities (“Operation Black Vote”), Riz Ahmed, a British actor and rapper of Pakistani parentage, appeared on a video. “Blacks don’t vote,” he said. “And by Black people, I mean ethnic minorities of all backgrounds.” The year before, the student union at the University of Kent attracted attention when it promoted Black History Month with the faces of six famous figures: Alongside four British people of African descent, it posted two of Pakistani heritage — the pop star Zayn Malik and Sadiq Khan, the mayor of London.

During its roughly two decades of prominence, the political Blackness movement, taking note of how Britishness had routinely been equated with whiteness, was especially devoted to the “Afro-Asian” alliance. (In Britain, the term “Asian” defaults to South Asian.) During the 1980s, the movement’s inclusive usage of “Black” went mainstream in Britain. The Commission for Racial Equality, a public body established in 1976, decided that “Asian” would be a subcategory of “Black”; other such organizations followed suit. The bien-pensant among the children of empire started styling themselves as Black, whether or not they had sub-Saharan ancestors.

Black, I mean nonwhite. Black, brown, red, or yellow.” Anyone who had been colonized or exploited by the Europeans qualified. And Malcolm X, in turn, was drawing on an internationalist tradition captured six decades earlier by W.E.B. Du Bois. “The problem of the 20th century,” he wrote, “is the problem of the color line; the relation of the darker to the lighter races of men in Asia and Africa, in America and the islands of the sea.”