Daniel Johnston, whose guileless, homemade recordings inspired dozens of musicians from Kurt Cobain to Lana Del Rey, has died at the age of 58.
The songwriter and artist "passed away of natural causes" at his home in Texas, said his family in a statement.
He was mourned online by those he inspired, including musician Beck and film star Elijah Wood, who called him "a gentle, beautiful treasure".
Producer Jack Antonoff praised the way Johnston had "shared fearlessly".
Born in California in 1961 and raised in West Virginia, Johnston became known as a songwriter after moving to Austin, Texas.
His reputation in the city grew after he started handing out cassette tapes of his no-frills home recordings to people in the street.
A cult figure on the local music scene, he gained wider exposure when MTV filmed a programme on the Austin music scene in 1985 for its series The Cutting Edge.
Johnston's performance brought him almost overnight acclaim, and his early home recordings received a belated vinyl release on the indie label Homestead.
He was never an accomplished player, and his pinched, high tenor vocals ensured he would never be a mainstream star - but the aching emotional sincerity of songs Life In Vain and True Love Will Find You In The End, earned him a fiercely loyal fanbase.
Kurt Cobain once described him as "the best songwriter on earth," and famously wore one of Johnston's t-shirts to the 1992 MTV Awards.
Other musicians who have covered Johnston's songs include Pearl Jam, Tom Waits, Wilco, Death Cab for Cutie, Sufjan Stevens and Yo La Tengo.
In 2013, Lana Del Rey and rapper Mac Miller each contributed $10,000 to fund a short film about the singer, with Del Rey recording a version of his song about heartbreak, Some Things Last A Long Time for the soundtrack.
Johnston was also known as an artist and comic-book writer, and his magic marker cartoon drawings were an inspiration for The Simpsons' creator Matt Groening.
In 1993, he was asked to turn Jeremiah the Innocent, the alien frog featured on the cover of his album Hi, How Are You, into a mural in Austin.
In 2006, his artwork was featured in a major exhibition at New York's Whitney Museum of American Art.
But Johnston was plagued by mental health problems, including bipolar disorder and schizophrenia, that hindered his career and endangered his life - including one incident where he attempted to crash a plane being piloted by his father.
A harrowing documentary, The Devil and Daniel Johnston, released in 2005, showed how fragile he had become, while bringing his music and story to a new audience.
"It sure was embarrassing," Johnston reflected in an interview with the Austin Chronicle. "Every terrible dilemma, every fabled mistake. Nothing I can do about it now, though. I wish they'd added a laugh track to it, because it sure is funny".
Johnston's own musical output had slowed in recent years and, following a farewell tour in 2017, he was largely confined to the family home.