The capitalized Black was first used, IIRC, in the 1960s by the Black Power movement and it leaked into popular usage (this is from my personal experience so I don’t have cites). It quickly became the preference over “Negro,” a term used as late as 1963 by Martin Luther King Jr. in his “I Have a Dream” speech.
I’m not sure when the B became b. Sometime after that came “African-American,” but “black” never completely went away. Now Black is back.
At both the English-language daily newspapers I worked at in Bangkok, the written guidelines covered this. At both of them, “Black” was capitalized, while “white” was not. Unless they both appeared in the same sentence, in which case both were capitalized.
There’s definitely a new emphasis on capitalizing the “B” in “Black”. I know, because I didn’t capitalize it throughout my last book, and the editors asked me if I had any objection to changing it to the capitalized form. I agreed, provided they didn’t simply use a simple “replace black with Black”, because there are plenty of others uses for the word.
“The Times also looked at whether to capitalize white and brown in reference to race, but both will remain lowercase. Brown has generally been used to describe a wide range of cultures, Mr. Baquet and Mr. Corbett said in their memo to staff. As a result, its meaning can be unclear to readers; white doesn’t represent a shared culture and history in the way Black does, and also has long been capitalized by hate groups.”
Hmm, I don’t generally see “blacks” or “Blacks” used as the primary noun for African peoples such as the Masai. Black Africans are typically just called “Africans”, or by an ethnonym or national term like “Masai”, “Nigerians”, “Yoruba”, “Congolese”, etc.
As I understand it, the anomaly that makes ethnonym choice challenging in the case of descendants of enslaved Africans is the fact that they were deracinated during their enslavement: taken out of their birthright kinship and ethnic and linguistic groups, and left with no easily identifiable ethnic heritage beyond being “black” or “African”.
Hence the emergence of the terms “black”, “Black”, and “African-American” (earlier “Afro-American”) as a kind of general stand-in for specific ethnic heritages. All or almost all Black Americans do share some particular ethnic heritage(s) with some African group(s), but nobody knows which anymore.
The term “brown”, on the other hand, seems to be a much more generic “umbrella” designation covering a whole lot of identifiable ethnic groups that do have distinct known ethnic heritages. So, for example, “brown people” may include Central Americans, South Asians, Pacific Islanders, Middle Easterners, and so on. It doesn’t really make sense in that case to treat “Brown” as an ethnonym in its own right.
Threadjack: The late, great Rush drummer Neil Peart took a bicycle trip through Cameroon in the late 1980s, and wrote his first book about it. One of his fellow travelers (ha) was a black man, and everywhere he went, the natives would ask him what tribe he was from. He couldn’t seem to explain to them that he didn’t know, and Americans blacks don’t do tribal identification anyway, and then it occurred to him to say he was from the California tribe. That placated them.