French filmmaker Sébastien Lifshitz first explored the hidden history of gay love in the 2012 documentary, Les Invisibles, which includes fascinating interviews with gay men and lesbians born between the two World Wars

Now, an accompanying photo book, The Invisibles: Vintage Portraits of Love and Pride, shares vintage photographs from the early twentieth century depicting various same-sex couples. "With each discovery I was stunned, for these images didn’t match the official history of homosexuality as it has been conveyed to us," says Lifshitz. "Despite the many battles and certain victories that ensued, the homosexual remained a victim in the collective consciousness; a hidden man. Yet, these images, which I've found through the years, were telling another story—one about a homosexuality without inhibitions, gentle and playful."

Of course, without corroboration from the subjects themselves, it's impossible to know exactly the nature of their relationships. But, says Lifshitz, that in itself is part of his fascination with the images: “It’s interesting to see homosexuality in everyone’s lives in some way,” he says. “It wasn’t an absolute taboo.”