He originally claimed to be Sean Tillmann's twin brother, Harold Martin Tillmann, from which he claimed his name originated. The name actually comes from a shopping center in Roseville, Minnesota, called the Har Mar Mall.
Tillmann was born in Marshall, Minnesota, on February 6, 1978 at Weiner Memorial Hospital. In 1987, his family moved to Owatonna, Minnesota. He graduated from the Perpich Center for Arts Education in Golden Valley, Minnesota. His family is still based in Owatonna, where his mother and father work as educators.
After playing in a number of garage bands throughout high school, Tillmann moved to Saint Paul, Minnesota, and joined three-piece noise band Calvin Krime as bassist and lead vocalist. Over the span of three-and-a-half years, they recorded two albums and an EP and regularly toured the country. When Calvin Krime disbanded in 1998, Tillmann explored his softer pop side in Sean Na Na, but, while the music was often pretty and upbeat, the lyrics were often unexpectedly dark. Tellingly, Sean Na Na performances often ended with dead-on renditions of popular R&B artist R. Kelly's "When a Woman's Fed Up." Reflecting on what led to the creation of the Har Mar Superstar character, Tillmann said, "I kinda always thought that (I was going to do R&B), I just had to figure out how to do it ... I just had to figure out how to make beats and write songs in that style."In 2000, Tillmann enlisted the help of several Saint Paul musician friends and the result was the pseudonymously self-titled album "Har Mar Superstar" that appeared on Kill Rock Stars in 2001.
If the music during this initial phase could be characterized as often tongue-in-cheek hip-hop, it was the sweaty, profane, and naked live shows that inspired the curious to see what others were talking about. Soon, Tillmann was touring all over the United States as Har Mar Superstar. Initially, he appeared onstage in a choir robe and was accompanied solely by pre-recorded beats emanating from his MiniDisc player. After his follow-up album, You Can Feel Me, elevated Har Mar's popularity in the United States and put him on the map in the United Kingdom, his stage outfits became more theatrical and several live shows featured female dancers. By the time the third album, The Handler, was released in 2004, Har Mar Superstar regularly toured with a drummer and a bassist to fortify the prerecorded material. Shows have ranged from club dates to festival engagements (Reading and Leeds Festivals).
In addition to his own headlining tours, Har Mar has opened for Ben Lee, The Strokes, Incubus, Tenacious D and the Yeah Yeah Yeahs. In 2007, Har Mar Superstar supported the Red Hot Chili Peppers on their tour of Australia and New Zealand. Fabrizio Moretti (The Strokes) and Tony Bevilacqua (ex-Distillers) have served as Har Mar's rhythm section, playing drums and bass guitar respectively. Har Mar supported Sia Furler on her 2008 tour with Denver Dalley on bass and Nick Slack on drums. Other bassists have included Jenni Tarma, Jeff Quinn, and John Fields, while Bert Thomas, Jeff Brown and Michael Bland have manned the drum stool.
As well as being a solo artist, Har Mar Superstar is a songwriter. He has written songs for artists including The Cheetah Girls, Jennifer Lopez, Kelly Osbourne, and Ben Adams. While "Tall Boy" was rejected by Britney Spears's management, Har Mar decided to record the song for his own album, Dark Touches.
In 2008, Har Mar Superstar was part of the live touring set-up of Neon Neon: the band created by Super Furry Animals' Gruff Rhys and producer/solo artist Boom Bip. Har Mar sings plus plays percussion during live shows and is featured on the recorded version and video of "Trick for Treat": a song on the band's debut album, Stainless Style, which was nominated for the Mercury Prize in 2008. Har Mar also performed backing vocals and appeared in the video for "Catch My Disease" by Ben Lee.
Har Mar's fourth studio album, Dark Touches, was released on October 12, 2009, in the UK and on October 13, 2009, in the U.S. Playing cities throughout the United States, Canada, and the United Kingdom in 2009 and 2010, Har Mar's "Dark Touches" touring band features Denver Dalley on guitar, Jeff Quinn on bass and Will Rockwell-Scott on drums.
In February 2011, Har Mar started recording and performing with the soft rock-inspired band Gayngs and experimental rock group Marijuana Deathsquads. Har Mar and Marijuana Deathsquads teamed up for month-long residencies in Los Angeles at Spaceland (February 2011), in New York City at Bowery Electric (October 2011) and in Austin, Texas (February 2012).
Har Mar and Father John Misty joined forces for a tour in May 2012. While Sean Tillmann and J. Tillman are not related, the tour was informally referred to as the "Two Tillman(n)s Tour." Har Mar performed material from his upcoming soul album "Bye Bye 17," and his band consisted of Macey Taylor on bass, Jeff Quinn on guitar, and J. Tillman on drums.
Har Mar's fifth album, Bye Bye 17, was released April 23, 2013 on Julian Casablancas' Cult Records. Tillmann toured the new material throughout the United States in March, April and May 2013 with Denver Dalley on bass, Jeff Quinn on guitar and Ryan McMahon on drums.
In August and September 2013, Har Mar Superstar supported his friends the Yeah Yeah Yeahs on various tour dates. Har Mar and Lizzo toured the U.S. in September and October. A 14-date tour of the United Kingdom followed in November.
At the end of 2014, Har Mar started writing song for a new album and toured the U.S. with The Pizza Underground (featuring Macaulay Culkin).
Collaborating once again with Julian Casablancas, Tillmann released his sixth Har Mar album – Best Summer Ever—on April 15, 2016. Best Summer Ever, since its inception, has been imagined as a "Greatest Hits of Har Mar Superstar from 1950–1985," even though Tillmann was born in 1978. Touring the United States & Europe in support of the new album, Har Mar has enlisted six other musicians to bring the songs to life.