Tar formed in 1988 by virtue of changing their name from Blatant Dissent, and scrapping most of the set. The original members were John Mohr, Mark Zablocki, Tim Mescher and Mike Greenlees. Enough songs were recorded for an album in 1988, and were eventually released as a single (Play to Win, No Blow, 1988) and an EP (Handsome, Amphetamine Reptile, 1989).

The band recorded for Minneapolis-based Amphetamine Reptile until 1992, after which they recorded for Chicago's Touch and Go label. Tom Zaluckyj replaced Tim Mescher at the beginning of 1991. Tar toured extensively in the US, less so in Europe. The band was brought to a conclusion through mutual agreement in 1995 after the recording of their fourth and final album, Over And Out. A final show was played Thanksgiving weekend, 1995 at Lounge Ax in Chicago.

The band briefly reformed at the request of the fine folks of the Premier Rock Forum, playing their BBQ in Chicago, on June 30, 2012. Then, at the request of the great Shellac of North America, another recital was given on August 26 of the same year at Lincoln Hall, also in Chicago. At the end of June, 2017, the band reformed again to play 2 nights at Bottom Lounge in Chicago benefitting the ACLU and Southern Poverty Law Center. At the end of November, early December 2018, the band played in Athens (Caledonia Lounge) and Atlanta (529) Georgia at the H2O50 festivities, then in Birmingham, Alabama (Saturn) on Dec 1. Tom was unable to attend the 2018 concerts. Filling in was good friend of the band, Dave Bychowski.