German driver Nico Rosberg held his nerve to win the Formula One championship for the first time after finishing second at the season-ending Abu Dhabi Grand Prix on Sunday.
Defending champion Lewis Hamilton won the race from pole position for his 53rd GP win.
Rosberg was 12 points ahead of his teammate coming into the title showdown and only needed to finish third, even if Hamilton won.
Hamilton blatantly disobeyed team orders to speed up near the end, thus backing Rosberg toward Sebastian Vettel and Max Verstappen in third and fourth places, respectively.
Vettel could not quite pass Rosberg and he finished third ahead of Verstappen.
Having finished runner-up for the past two seasons, the 31-year-old Rosberg finally emulates his father Keke Rosberg, who won the F1 title in 1982.
"That was definitely not the most enjoyable race I've had. Can't believe it's over. I'm ecstatic," Rosberg said.
Hamilton, meanwhile, misses out on a third straight title and fourth overall, despite ending the year with 10 wins - one more than Rosberg.
Hamilton slowed in the later stages of the race to increase the chances of Rosberg being overtaken by other drivers. If Rosberg had been passed by Vettel and Verstappen and had finished fourth, then Hamilton would have held onto his title.
When his team told him over race radio to up the tempo, Hamilton replied bluntly: "I suggest you guys let us race."
Even a direct order from Mercedes' executive director Paddy Lowe four laps from the end did not work.
Rosberg was clearly getting nervous, and Vettel was a wheel's length away from him on the final lap.
But he kept his cool and his elation was evident as he let out a delighted screech of "Yes! World champion" when he crossed the line.
Then he jumped out of his car and danced around the track before being hugged by his mechanics.
Hamilton made a point of coming over to congratulate Rosberg and offered him a hug. Rosberg accepted but it was a brief one, and then he carried on celebrating as he was tossed into the air by his Mercedes crew.
He then grabbed Formula One supremo Bernie Ecclestone and lifted him into the air, while Ecclestone congratulated him.
Hamilton stood in the corner sipping water as Vettel - himself a four-time F1 champion - smiled and congratulated Rosberg.
On the podium, Rosberg's eyes were watering as the weight of his achievement sank in and he thanked his wife, who also wiped away tears.
"A big congratulations to Nico. Good job man," Hamilton said, and they shook hands more enthusiastically this time.
"Congrats to Lewis, you are a great competitor," Rosberg said.
Rosberg survived the tense finale of the race as well as earlier drama when he was close to colliding with Verstappen on lap 21 as they jostled for second place.
With the sun setting on the Yas Marina track, the race started with Hamilton on pole for the 12th time this season " a career best " and 61st overall, four behind Brazilian great Ayrton Senna.
Hamilton got away cleanly, as did Rosberg - albeit cautiously. Meanwhile, Verstappen's car went into a spin following contact shortly after the start, dropping down from sixth to last, but soon caught up.
Hamilton came in for his first tire change on the eighth lap, and Rosberg came in for his on the next lap.
But the German driver was held up for a couple of seconds by Vettel, who had just come in for his stop, and when he came out, he was behind Verstappen and Hamilton.
Rosberg needed to overtake Verstappen to get closer to Hamilton, but his team told him not to take any risks.
Verstappen, the youngest driver to win an F1 race, has earned a reputation for his risky, borderline dangerous overtaking and has upset other drivers this season.
As he and Rosberg jostled for second place, they twice almost came into contact, and Rosberg must have been mightily relieved to see him pitting shortly after.
He was back on his tail later on, but Vettel was between them and he didn't get another crack at Rosberg.
Last season, Hamilton sealed the championship in style with three races to spare, while in 2014 the title also went down to the final race in Abu Dhabi. However, Rosberg was in contention then because of a double points rule that applied only to the final race and has since been scrapped.
After losing last year's title, the German driver won the final three races of the campaign and the first four of this year to show Hamilton that he meant business.
As Hamilton struggled with engine problems early on, Rosberg looked in command as he opened up a lead of 43 points.
The topsy-turvy campaign saw Hamilton bounce back to lead Rosberg by 19 points heading into the summer break.
Rosberg then turned the tables on Hamilton to lead again by 33 points, only for Hamilton to respond with three straight wins to trim that to 12 heading into their Abu Dhabi showdown.
Last-race scenarios are nothing new to Hamilton and this was fourth time he has been involved in such a finale.
He won on the last day of the season in 2008, beating Brazilian Felipe Massa by one point in a dramatic final race.
The previous year, Hamilton was the one feeling bruised as he lost the title by one point to Ferrari's Kimi Raikkonen.