Homosexuality, as we understand the term today, was coined in the nineteenth century. Individuals practicing same-sex sexual relations (particularly men) have been prosecuted for crimes like "buggery" and "sodomy" in Western countries since at least the 15th century, and likely much earlier. I recently recommended this book in this subreddit elsewhere, actually, but you should check out Anna Clarke's book "Desire" for a clearer history of sexuality.