After Governor Mark Dayton signed a marriage equality law passed by the legislature last week, Minnesota became the twelfth US state to legalize same-sex marriage.
In an outdoor public signing ceremony surrounded by throngs of people, Dayton signed the measure then posted a photo of the event to his Twitter account with the short tweet: "It's history."
The law will go into force on August 1, state officials said, making the northern US state the third in two weeks to legalize same sex marriage, after Rhode Island and Delaware.
Minnesota will be the second midwestern state to recognize gay marriage after Iowa, but constitutional bans against gay marriage remain in place in 31 of the 50 US states.
The US Supreme Court is expected to issue a ruling next month on whether or not the Defense of Marriage Act, under which the federal government recognizes only heterosexual marriages, is constitutional.