Year legalized: 2009
How it happened: Sweden -- one of the first countries to give gay couples legal "partnership" rights in the mid-1990s -- legalized same-sex marriage by a landslide parliamentary vote of 226 to 22 (a whopping 70 percent of Swedes polled before the passage of the new law supported gay marriage). Several months after the approval of the bill, the Lutheran Church of Sweden voted to allow gay weddings. Priests had a right to refuse to perform these ceremonies, but if they did the church would find another member of the clergy to officiate.
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