Four winters ago, Justin Vernon retreated to his father's secluded cabin in northern Wisconsin, purging his sorrow through a falsetto that no one would probably ever hear. He spent three brutally cold months alone, piecing songs together using antiquated recording equipment. "It feels good not to be there," Vernon says now. "But I feel proud that I had to go through some of that stuff."

Three winters later, Vernon found himself in another confined space, but no longer alone. He was at Avex Honolulu Studios on the Hawaiian island of Oahu, where Kanye West was recording in early 2010. He shared a room the size of a closet with Miami rap star Rick Ross and helped construct "Monster," perhaps 2010's strongest hip-hop posse cut (it peaked at No. 18 on the Billboard Hot 100), while smoking, according to Ross, "some of the best weed the world has to offer."

It took Vernon, the 30-year-old mastermind of the band known as Bon Iver, a frozen season in solitude to find his voice. It took Ross less than an hour to recognize its power.

"He's a fucking genius," Ross says. "I'd never seen nor heard of him in my life, and I looked up, and I was in a fucking 5-by-5 room with a white guy, smoking weed . . . and his voice is like something I've never heard, and he's using words that are far from common. Within 20 minutes, I realized why Kanye had him there."

How does a pale, bearded folkie like Vernon draw a line from Eau Claire, Wis., to the Aloha State? Vernon's (unwitting, according to him) plan was two-pronged. First, he earned the admiration of the indie blogosphere with "For Emma, Forever Ago," the nine-song by-product of his three-month sojourn featuring little more than an acoustic guitar, a few bass drum kicks and lilting vocals that packed devastating emotion. After a 2007 self-release, "Emma" was rereleased on Jagjaguwar in 2008 and became the indie label's biggest album ever -- 323,000 copies sold, according to Nielsen SoundScan.

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Vernon's next move was to become a songwriting Swiss army knife, through an array of side projects, production contributions and high-profile indie collaborations -- from contributing to 2009's "Dark Was the Night" charity compilation to writing a track for the "Twilight: New Moon" soundtrack -- all of which eventually led to an admiring call from West in January 2010. Fifteen months later, Vernon was sharing the spotlight with West during his headlining Coachella set, hours after having joined indie act the National onstage.

"Bon iver" is a take on the French phrase "bon hiver," meaning "good winter." Vernon says that "Bon Iver, Bon Iver," his sophomore album due June 21 on Jagjaguwar, is his "spring record." It's a 10-song collection that replaces the sparseness of "Emma" with lush arrangements. (Vernon now shares the Bon Iver name with multi-instrumentalists Sean Carey, Michael Noyce and Matthew McCaughan, but still handles the songwriting.)

Jagjaguwar is finalizing a rollout plan with big-box retailer promotion and official music videos. According to Bon Iver's co-manager, Kyle Frenette (also founder of Amble Down Records), "The stakes are a lot higher all around: the marketing, the touring, the band, everything." But for the man in the middle of it all, "Bon Iver, Bon Iver" is the next step of his journey away from that Wisconsin cabin. "This is the record I wanted to make my whole life," Vernon says. "Lyrically, it's an extension of 'For Emma.' It's like, what happens when you leave that place? You don't necessarily arrive somewhere new right away."

The tale behind the creation of "Emma" is indie folklore by now. While reeling from mononucleosis, a breakup with a girlfriend and the dissolution of his longtime alt-country band DeYarmond Edison in 2006, Vernon moved back to Wisconsin from Raleigh, N.C., to sort out his life. Less heralded is the way Vernon and his team utilized that story to attract listeners.

In 2007, Vernon adopted the Bon Iver pseudonym, and the entirety of "Emma" was posted on Myspace, along with 400 words that detailed the singer/songwriter's isolation. Music sites like Pitchfork and Stylus magazine chronicled the singer's journey in positive reviews, and after Vernon signed to Jagjaguwar in October 2007, the free stream remained active alongside the bio until "Emma" was officially released the following February.

"Listening to the music and reading the mythology just fits so well together and really pulls on people's heartstrings," says Nate Vernon, Justin's younger brother and his co-manager since 2008. That buzz grew as Vernon toured in 2008 and the album made the year-end critics' lists of Spin, NME and Q. After debuting at No. 181 on the Billboard 200 upon its Jagjaguwar release, the album peaked at No. 64 in its 11th month. "The way 'For Emma' grew was from a serious amount of word-of-mouth," Jagjaguwar owner Darius Van Arman says. "Our job was to not get in the way of that."

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