Last month, Washington, Maine and Maryland became the first states to pass same-sex marriage by popular vote.
They joined six other states – New York, Connecticut, Iowa, Massachusetts, New Hampshire, Vermont – and the District of Columbia that had already enacted laws or issued court rulings permitting same-sex marriage.
About 140 couples had registered to marry at Seattle City Hall, which had set up five separate chapels to accommodate the revellers.
Cheers and applause regularly broke out as another couple's marriage became official.
''We're totally thrilled," said Keith Bacon, who celebrated his six-year anniversary with Corianton Hale the night before.