Before the 1970s, erotic male imagery was very much a fringe area of photography, part of a homosexual culture that was still very much an underground ghetto. Rather than being openly homosexual, it centred on ideals of body culture and body building.
It was the series of ads for Calvin Klein, beginning in the late 1970s, that Weber hit the magazines with his often near naked, seemingly casual and highly eroticised images of men - and occasionally women.
Bruce Weber most certainly did not invent homoerotic photography, he very forcefully put it into the world of mainstream publications through his advertising and fashion work.