The Kings, who had led the best-of-seven championship series 3-0 before dropping two straight games, completed a four-games-to-two triumph.
Dustin Brown had a goal and two assists, Trevor Lewis and Jeff Carter scored two goals apiece and goaltender Jonathan Quick made 17 saves en route to earning the Conn Smythe trophy as the playoffs' most valuable player.
Afterwards Quick said he believed that,†in a city where the NBA's Lakers have been perennial title contenders and the Los Angeles Dodgers a beloved baseball institution, a championship would good for ice hockey.
"Obviously you still go about your day the same way you always have," Quick said.
"I think the attention the team's going to get is great. That's something we have been looking for in this market for so long, is to get that attention towards hockey. It's just an honor to be on this team. I'm glad to be a part of it."
The Devils had become the first team since 1945 to go down 0-3 in the finals and hold on to force a sixth game, and their two wins had raised the question of whether the Kings would join the 1942 Detroit Red Wings as the only team to blow a 3-0Stanley Cup Finals lead.
That fear was virtually over by the end of the first period.
Thanks to a five-minute major penalty meted out to New Jersey forward Steve Bernier for boarding 11 minutes into the game, the Kings scored three power-play goals to seize control.
Brown scored the first, charging the net and re-directing Drew Doughty's shot for a 1-0 lead at 11:03 of the first.
He then assisted on a goal by Carter, coming from behind the net and firing toward Devils goalie Martin Brodeur a shot that Carter directed into the net at 12:45. Lewis made it 3-0 at 15.01 of the first.
Carter added another 1:30 into the second period, beating Brodeur with a wrist shot before the Devils' Adam Henrique got New Jersey on the board at 18:45 of the second.
Lewis added another goal at 16:15 of the third, and Matt Greene tacked on one more less than a minute later against the stunned Devils.
The Kings' triumph comes after a stuttering regular season saw them replace coach Terry Murray with Darryl Sutter in mid-campaign.
Sutter, who became the fifth mid-season replacement coach to win the Stanley Cup, said December "seems like a long time ago."
"You know what, you look at the big picture now, and I was right on how I thought about what type of players these guys were," he said.
But Los Angeles stormed to the Western Conference crown. They needed just 14 games -- matching an NHL record -- to reach the championship series for the just the second time in their 45-year history, the first coming back in 1993.
They ousted top-seeded Vancouver in five games in the first round, swept St. Louis then eliminated Phoenix in five games.
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