Joined by Brandi Carlile, Marcus Mumford and other artists, Mitchell played guitar, told stories, and sang a dozen songs in a surprise Newport headlining performance on Sunday

"I just realized, Joni’s the least nervous person up here,” exclaimed Brandi Carlile halfway through a history Newport Folk Festival set that paid tribute to Joni Mitchell, in her first full set-length concert appearance in two decades.

Over 13 songs, Mitchell, who last appeared at the festival 53 years ago, in 1969, held court as a star-studded crew of musicians (Carlile, Blake Mills, Lucius, Wynonna, Celisse, Taylor Goldsmith, Marcus Mumford, and many more) sat around on couches on-stage playing a mix of her favorite oldies (“Why Do Fools Fall in Love,” “Love Potion No. 9”) as well as an array of Mitchell masterpieces.

Sitting in a throne, Mitchell began the set by occasionally singing along to her own songs, accompanied by vocalists like Carlile, (“Carey”) Goldsmith (1991’s “Come In From The Cold”) and Celisse (“Help Me”). But by the end of the hour-plus performance, the 78 year-old singer who only recently sang on stage for the first time in nearly a decade had stood up, played a lengthy guitar solo (“Just Like This Train”) and sang a moving baritone lead vocal on Gershwin’s “Summertime'” as well as tear-jerking takes on “Both Sides Now” and “Circle Game.”

The premise: Recreating the recently infamous “Joni Jams,” the informal A-list gatherings of musicians at Mitchell’s Los Angeles home in recent years, where everyone from Carlile to Elton John to Herbie Hancock to Bonnie Raitt gather around Mitchell and trade songs and stories in the years following Mitchell’s aneurysm. “No one brings folk singers together like the humility of trying out a new song in front of Joni fucking Mitchell,” as Carlile, who curated and organized the entire set, explained in the introduction to the performance.

At the end of the set, Carlile pronounced the night’s eternal importance: “Joni Mitchell,” she proclaimed, “has returned.”