Let me spell it out. Homosexuality came about when people turned their backs on God and followed their own warped desires, which led to all kinds of evil behaviour, including idolatry and the pursuit of the base sexual desires that God forbade. (There's no greater idolatry than the worship of the self).
The cult of Semiramis was one of such, whose influence later spread throughout the world and can be observed in various pagan religions in ancient Babylon, Egypt, Greece, Rome, etc. The effects of such pagan influence became part of their culture and has been passed down the generations even until the current day.