I think, the most important thing that should be noted here, in relevance to historical accuracy, is that homophobia didn't really seem common outside of Europe, and that in Europe itself the main two cultures that propagated it were the Romans and the Vikings(in both cases because they considered it bad to lower yourself as a man to the level of a woman).
From what I understand the Hebrew community broke their brains over it because a man can't own a man, like they can own women.
(The Christian church is suspected to have appropriated the three cultures above. In a similar sexual note, medieval Christian writings describe the bond between God and the highly religious to be an erotic one)
In Greek culture, however, the notion was that love between men was more pure because they were more real people than women. Both Greece and Japan practised pederasty, where an older man gave 'practical sex-ed' to his student. Then there's China where homosex seemed common and accepted, but I don't recall if there were such a thing as gay marriage.
Finally, if you look at tribal cultures, ones that use a Shaman, Homosexuals and Transgendered people were considered ideal to be Shamans, because they considered them double-souled in their dualistic nature.
One of the things I would like to point out here is how male homosexuality is regarded next to how women are regarded in a culture. I would also like to point out that in the last FotF posts Toady has made, he said that in the design plans, Dwarves have very strong gender equality.
The last thing that I would like to share with you is the
Kingsey scale. I also want to note that in the Sims, all sims are just programmed to be bisexual, becoming more homosexual or heterosexual depending on their romantic interactions with other sims of both genders.
Personally, I would like some rudimentary sexual variation in dwarves, because hey, they also have tastes, but I wonder to what extent sexuality can be modelled in dwarf fortress(Transgender dwarves? Asexual dwarves? Pansexual dwarves? And the influence of stds or I guess in DF terms SSs).