The Red Sox hadn't won a World Series at home since Babe Ruth was on their roster and they joined the 1991 Minnesota Twins as the only teams to win the World Series a year after finishing in last place in their division.
"We did it," said Boston second baseman Dustin Pedroia of the Red Sox four games to two victory in the best-of-seven series.
Boston baseball fans rejoiced in the club's eighth Major League Baseball championship in franchise history, packing the streets around the Fenway Park stadium and spilling out of bars and restaurants onto Boylston Street and Yawkey Way where they danced and sang into the early morning hours.
The triumph was particularly sweet and welcome for a city traumatised by the Boston Marathon bombings in April which killed three people and injured more than 260.
"God never left his kids alone," said World Series most valuable player David Ortiz. "This is a city that has been through a lot of situations.
"And sometimes bad things got to happen for us to get the message. And we got the message. Everybody stayed together."
Red Sox general manager John Farrell said the city's Boston Strong message was taken to heart by the players.
"In a time of need, in response to a tragedy I go back to our players understanding their place in this city," said Farrell. "They get that there's a civil responsibility that we have wearing this uniform, particularly here in Boston.
"And it became a connection the way our guys reached out to individuals on our hospital visits. And it continued to build throughout the course of the season.
"Everybody in our uniform will look back on the events that took place and the way things unfolded as a special year," Farrell said.
The fans, the players and the league have been waiting a long time for a World Series Beantown bash.
The last time the Red Sox clinched a title at Fenway Park, a 23-year-old Ruth was an eighth-inning defensive replacement.
Fast forward to Wednesday where Shane Victorino was the game six hero. Victorino, who missed the previous two games with a back injury, blasted a three-run double in the third inning and Stephen Drew clubbed a solo homer in the fourth for the Red Sox.
Victorino hit a three-run double off Cardinals starter Michael Wacha to open the scoring for the Red Sox in the bottom of the third. The right fielder doubled off the left field Green Monster wall, which scored Ortiz, Jacoby Ellsbury and Jonny Gomes.
Victorino extended Boston's lead to 6-0 with an RBI single with the bases-loaded in the fourth in front of a Fenway crowd of 38,447.
Slugger Ortiz tormented the Cardinals all series with a hot bat, finishing 11-for-16 at the plate in the Series and had seven walks to tie Carlton Fisk's 1975 club record.
"I am back baby," Ortiz said during the post-game celebration where he was presented with the MVP trophy.
St. Louis wasn't going to give Ortiz a chance to punish them further in game six as they walked him in his first three at bats of the contest.
Battled-tested Boston starter John Lackey hurled 6 2/3 innings of one run ball, striking out five and walking none.
Right-hander Lackey clinched a World Series title for the Angels back in 2002 with a terrific game seven performance as a rookie.
"I am really fired up to be part of this. It is really cool," Lackey said. "It has been a fun group from day one to be around. We busted our butts to get here."
Japan's Koji Uehara recorded the final out of the contest, striking out St. Louis lead-off hitter Matt Carpenter.
The Red Sox made quick work of Cardinals rookie starter Wacha, who left the game after giving up four runs on six hits in just 3 2/3 innings of work.
Boston has now won three titles in the last 10 years but their previous two came on the road. In 2007 they beat Colorado and in 2004 they snapped an 86-year title drought with a four-game sweep of the Cardinals.