Mikaela Shiffrin becomes first skier to win slalom, giant slalom, Super-G and overall World Cups in one season with 17-year-old New Zealander Alice Robinson in second.
Mikaela Shiffrin makes history. Again.
She only needed to finish Sunday's World Cup Finals giant slalom to clinch the series title.
But that was never going to be enough for the double Olympic alpine skiing champion.
"I went for it. When I woke up this morning, I was thinking I want to ski a really good giant slalom. I want to be aggressive. I want to take some risks and earn the globe. I wanted to really deserve that and it's incredible." - Mikaela Shiffrin after winning in Soldeu to clinch the giant slalom World Cup title
The 24-year-old triumphed yet again in Soldeu, Andorra, beating 17-year-old New Zealander Alice Robinson by three-tenths of a second with Petra Vlhova third.
Shiffrin fought back the tears after collecting her fourth crystal globe at the end of an incredible season in which she also won an unprecedented fourth consecutive slalom world title.
As well as extending her record World Cup wins tally for a season to 17, she is now the first skier to win slalom, giant slalom, Super-G and overall crystal globes in the same campaign.
"There were many moments the last eight years that I was thinking maybe I would never get this giant slalom globe, so it was a lot of emotions to finally celebrate that in the finish."
Shiffrin led Petra Vlhova by 97 points going into the final giant slalom of the season.
That meant the only way the Slovak could take the title was by winning the race with Shiffrin failing to finish.
Both eventualities looked unlikely after the first run as the American went quickest, 0.59s faster than Viktoria Rebensburg with New Zealand's Alice Robinson in third and Vlhova fourth.
Vlhova took the lead with an excellent second run but Robinson, world junior giant slalom champion last month in Val di Fassa, moved ahead of her to secure her first World Cup podium finish.
"Alice skied amazing today, she was attacking both runs. She did amazing ski the first run and she backed it up with a really amazing performance and now she has her first World Cup podium. That's super cool," said Shiffrin.
Rebensburg looked set to go into the lead but Germany's 2010 Olympic champion ran wide with just a few gates to go, losing all her speed and dropping out of the podium places.
Shiffrin led Robinson by 0.84s after the first run and, despite a notable mistake halfway down, was able to come home in front by three-tenths of a second for her 60th career World Cup win.
Vonn (2010 and 2012) and Tina Maze (2013) also claimed four World Cup titles in a season, but their quartets included the rarely-raced combined.
Unlike Maze, who set a record points score in 2013 (2414), Shiffrin, who has amassed 2204 points, has taken short breaks during the campaign including after last month's World Championships in Are, Sweden.
And she believes that policy has proved effective, meaning she "had energy for today".
Shiffrin also revealed that she is looking forward to getting away from the slopes.
"I'm going shopping in Barcelona tomorrow or the next day."
Shiffrin smashed Vreni Schneider's record of 14 World Cup wins in a season which the Swiss set 30 years ago.
And as Schneider told Olympic Channel last month, "There are worse things than being beaten by Shiffrin!"
"She is so superior technically. And she has an amazing feeling for the snow regardless of what the conditions are."
"If she stays healthy, she will break many more records, she is still so young. She is a very nice person, very authentic and very down to earth."
On Saturday, Shiffrin equalled Ingemar Stenmark's record of 40 World Cup slalom victories.
The Swede has the all-time record for World Cup wins with 86, and he has little doubt that mark will fall to the all-conquering American.
"I think that Shiffrin will win more than 100, and it doesn't make me sad at all." - Ingemar Stenmark