It wasn't just the Blacks who had to sit at the back of the buses and drink out of seperate drinking fountains; Hispanics also could not do those things or eat in a white restaurant.
And it wasn't too long ago that Blacks and Hispanics had to pay a "poll" tax in order to vote. This effectively kept the minorities from voting in presidential and other important elections.
The Columbia Encyclopedia says:
...in 1964 the 24th Amendment to the U.S. Constitution disallowed the poll tax as a prerequisite for voting in federal elections. In 1966 this prohibition was extended to all elections by the U.S. Supreme Court, which ruled that such a tax violated the “equal protection” clause of the 14th Amendment to the Constitution.
Even some churches were segregated so that minorities could not go worship in them.
Did you forget someone else? You forgot to include the whites. Was that just an oversight or was there some other reason for excluding them?
I recall an article written by a black professor, a Catholic with a French-looking last name (so maybe a native of Louisiana), in which he remembered attending Mass in a church where blacks were restricted to the last pew.
I don't know that much about how Hispanics were treated in places where there was segregation, but many of them considered themselves and were regarded as white (at least those without obvious Indian or African ancestry).