I'll start off by saying that you don't bring anything to the table that makes the game uncomfortable or not fun for the players. And try not to disallow character concepts in the name of preserving historical "accuracy." You will often be surprised at just how much certain marginalized people were able to accomplish despite having the deck stacked against them.
I don't run a lot of historical games (Deadlands is not a historical game), but the one I do run most frequently would be Call of Cthulhu set in the United States during the 1920s and 1930s. And in case you're unware, this era is widely considered the nadir of race relations in the US. I wouldn't feel comfortable running a campaign set during the era where I completely ignored the rampant racism, sexism, homophobia, etc., etc. But at the same time I wouldn't have player characters constantly having to deal with those kinds of issues every day.
I ran a Trail of Cthulhu game set in New York during the 1930s. As part of their investigation, the PCs tracked down the person who contacted the police about a missing women he found on the grounds of the construction job he was working. This worker was a black man, and during the course of their interview they asked him why he fled the scene before authorities arrived. He answered, "I'm from Georgia originally. And where I'm from, a Negro found in the vicinity of a nude white woman is not long for this world." I liked this scene because it established a few things: It made it clear to the PCs that the 1930s were not the same as 2016. And that this construction worker was a good man willing to risk his own well being to help a stranger in distress (he fled the scene but he made sure the missing women got the help she needed first).
There are some things I won't do. I typically won't use racial slurs, in part, because it makes me uncomfortable and I'm sure nobody else at the table wants to hear them. It may be realistic, but it most decidedly would not be fun for anyone of us. I might have the PCs run up against someone who is racist or sexist, but not all the time and I won't allow it to get in the way of their character participating in the game.