Doug Ireland has an interesting article on the subject in the latest issue of Gay City News.

I think he is overstating the libertarian influences on Swedish socialism, but I guess that is what it looks like from an American perspective. The truth of the matter is that Sweden did not have anything even resembling a libertarian attitude towards gays until very recently. Swedish Communists did not embrace a gay-friendly agenda until the late 1970s, and the Social Democrats did everything in their power to humiliate gays and lesbians well into the 1990s.