Mark Kozelek was born and raised in Massillon, Ohio. Upon relocating to Atlanta, Georgia, he met drummer Anthony Koutsos. After the pair moved once again to San Francisco, California, Red House Painters formed with the addition of guitarist Gorden Mack and bassist Jerry Vessel. From 1992 to 1996, Red House Painters released a series of acclaimed albums, showcasing Kozelek's intense, highly autobiographical songs. However, Kozelek's parting with the record label 4AD, followed by a major label merger which left Red House Painters' 1998 album Old Ramon on the shelf, proved highly frustrating and stifled the group's momentum. Kozelek opted to occupy himself with a series of idiosyncratic solo recordings as Red House Painters dissolved.
Sun Kil Moon debuted with Ghosts of the Great Highway in 2003, and also features former RHP members Jerry Vessel and Anthony Koutsos as well as new collaborators Geoff Stanfield (formerly of Black Lab) and Tim Mooney of American Music Club. Their follow-up effort appeared in 2005 on Kozelek's newly formed label, Caldo Verde Records. Titled Tiny Cities, the album is made up entirely of covers of songs by Modest Mouse. Once again, Kozelek's cover versions varied greatly from the originals.
Kozelek returned in 2008 with the release of Sun Kil Moon's third album April. The album features 11 brand new recordings, including guest vocal contributions by Ben Gibbard, Will Oldham, and Eric Pollard. On December 9, 2008, Kozelek and Caldo Verde Records issued The Finally LP, a CD collection of 10 unreleased tracks, including covers of songs by Stephen Sondheim, Will Oldham, Hüsker Dü, and Low among others, as well as two previously unreleased instrumentals. Two newly-recorded live albums, Find Me, Ruben Olivares: Live in Spain and Lost Verses Live, followed in spring 2009.
On April 23, 2010, the release of Sun Kil Moon's fourth album, Admiral Fell Promises, was announced. The album was released on July 13, 2010. Kozelek, who acted as record producer on every album released by his bands Red House Painters and Sun Kil Moon as well as his solo releases, produced the debut album by friend and Low singer-guitarist Alan Sparhawk, in Sparhawk's side-project Retribution Gospel Choir. Kozelek has also dabbled in acting—friend Cameron Crowe cast him in Almost Famous (1999) as Larry Fellows (the bass player in Stillwater), and Vanilla Sky (2001). In 2005, he appeared in Steve Martin's film Shopgirl, playing a musician who befriends and mentors Jason Schwartzman's character. Kozelek also performed "Lily and Parrots" (a Sun Kil Moon song) live in the film.