An estimated 3.2 million people packed the 7-mile parade route on a raw and rainy autumn day, standing in dense crowds, leaning from windows and cheering from rooftops.
Some held signs bearing words of thanks, marriage proposals and expressions of wonder at the team's achievement after 86 years of dashed hopes since its last championship in 1918.
"All is forgiven," read one banner.
"Now we just have to wait for the other six signs of the apocalypse," said another.
And dozens said simply: "Thank you."
Red Sox pitcher Derek Lowe, a former Mariner, said,
"It started raining and it was cold and the people didn't even care. They've waited a long time. You'll never see a parade like that with so many people, no matter what sport or what city."Police said 15 people were arrested, 12 were taken to the hospital for treatment of injuries and 30 were treated on the street.
Pitcher Pedro Martinez was hit in the forehead by a baseball.
"I have a little headache, but I'm OK," he said.