Earlier quoted context omitted.
>Although were there really no cultures in that era that allowed same sex marriage? No Christian cultures, obviously.
Was there any historical culture in which same-sex marriage was common or accepted? I can’t think of one, Christian or otherwise (though I can think of a couple of examples of same-sex people got married by subterfuge).
Homosexual activity cannot result in biological children so there was really never any society that considered anything like homosexual marriage until our own. The main reason for marriage was to control sexual unions and the children who might result from them. In societies which had marriage (many had no such concept) homosexual marriage didn't make much sense.
The wikipedia article on historical same-sex unions mentions that some cultures had rituals around cementing homosexual relationships but those wouldn't be considered the same as marriage, they'd be more like any pre-sexual / pre-relationship rituals. Marriage typically is about the sharing of finances, responsibilities, the raising and rights of children, etc. And none of the examples in the wikipedia article on historical same-sex unions concerned any of these.