Pop superstar Swift, still only 25 years old, won four of her whopping 10 nominations, including Video of the Year for "Bad Blood" with Kendrick Lamar and Best Pop Video for "Blank Space."
She buried the hatchet with rapper Nicki Minaj, embracing her former foe on stage during a brief rendition of "Bad Blood" dressed in a red tassled mini-dress and presented West with a career achievement award.
Cheered by his biggest fan, pregnant wife and reality star Kim Kardashian in a lace-up dress that left little to the imagination, West appeared moved - but not humbled - by an extended standing ovation.
Winning MTV's Video Vanguard lifetime achievement award was a significant milestone for West, previously given to greats such as Madonna, Michael Jackson and Beyonce.
"I have decided in 2020 to run for president," he announced at the end of a rambling address in which he also appeared to confess to smoking marijuana before taking the stage.
"I will die for the art, for what I believe in and I ain't always gonna be polite," he said. "I rolled up a little something. I got the answer," he said. "We're the millenials bro."
The 38-year-old boundary-pushing rapper also won best Video With a Social Message for "One Man Can Change the World" with Big Sean and John Legend.
Host was shock pop diva Cyrus, who lived up to her reputation by flashing her left breast and nipple, letting a curtain drop backstage at an opportune moment.
She closed out the Los Angeles show with a performance that saw a firework set off from her crotch and announcing that her new album, Miley Cyrus and her Dead Petz, was out for free online.
The website promptly crashed and on twitter she directed her 22 million followers to her regular website, where the music was available.
Cyrus made MTV award history two years ago by twerking on stage with Robin Thicke in a flesh-colored bikini and cavorting around with a foam finger.
On Sunday, she wore a revolving door of outfits for the broadcast, but walked the red carpet in an outfit so revealing that the New York Daily News named it a "crotch chandelier."
But if Minaj hugged and made up with Swift, she went into battle with Cyrus for telling The New York Times in a recent interview that Minaj was "not too kind" and "not very polite."
"This bitch that had a lot to say about me the other day in the press, Miley," said the rapper, after thanking her pastor and winning Best Hip Hop Video for "Anaconda."
The camera panned to a non-plussed Cyrus, who stayed civil. "We're all in the industry, we all do interviews, and we all know how they manipulate."
The surprise start to the show was Swift joining a resplendent Minaj, festooned in a red tribal-style headdress, in an opening set.
They hit the headlines last month when Minaj's "Anaconda" was passed over for a Video of the Year nomination.
Minaj blamed the slight on bias against full-figured black women, saying the music industry preferred "very slim" women.
The very slim Swift responded by telling Minaj "I've done nothing but love and support you" and invited her to share the stage.
Nearly two days later, Swift apologized. Minaj said she wished that Swift had spoken out on portrayals of African American women.
The first MTV awards were handed out in 1984. Winners receive a statuette of an astronaut on the moon, known as a "Moonman" award.
Winners in other leading categories were Fall Out Boy for Best Rock Video with "Uma Thurman," Song of the Summer went to 5 Seconds of Summer for "She's Kinda Hot" while Mark Ronson and Bruno Mars won Best Male Video for "Uptown Funk."
Artist to Watch went to Fetty Wap for "Trap Queen."