Bon Iver's Justin Vernon and The National's Aaron Dessner hosted the second-annual Eaux Claires Music and Arts Festival located in Justin's hometown of Eau Claire, WI this past weekend.

The weekend was full of collaborations, surprise guest appearances, and other exciting things like the live debut of Bon Iver's new album, 22, A Million, which drops September 30 via Jagjaguwar. You can watch a video of the full set:

One of the most anticipated performances of the weekend was the Grateful Dead tribute, the only planned live show to support that five-hour Dead tribute album that was spearheaded by The National. In addition to members of The National, the live tribute included Arcade Fire's Richard Reed Parry, Jenny Lewis, Bonnie "Prince" Billy, Phosphorescent, Lisa Hannigan and more. "Birdsong" and "Ripple" were played during the set, as well as many others:

Members of The National are also backing the Dead's Bob Weir for a new album and tour, which includes three NYC-area shows.

Phil Cook brought a few friends onto the stage during his performance as well, including Bruce Hornsby with Justin Vernon and Lena May Perry:

The weekend closed out with a surprise appearance by Chance the Rapper during Francis and the Lights' set. Chance played played his very Justin Vernon-ish Francis and the Lights collab "Summer Friends" which then transitioned into the real Justin Vernon, Francis and the Lights and Kanye West's song "Friends". Justin came out for it, and Chance filled in for Kanye, plus there was some pretty crazy choreography going on:

Beach House, Deafheaven, James Blake, Melvins, My Brightest Diamond, Tenement and still much more. Pictures are in the gallery above. Check out some Twitter love from festival attendees:

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