After a period of legal troubles which prohibited the band from using its own name on recordings, Black Flag returned to the studio with a new approach to its music that incorporated a greater variety of styles, resulting in a sound orthodox punks found difficult to accept.

The line-up had shrunk from five members to three: vocalist Henry Rollins, drummer Bill Stevenson, and co-founding guitarist Greg Ginn.

The A-side of the LP is composed of six generally high-paced, thrashy hardcore tracks, featuring guitar solos unusual in punk music.

The band members had grown their hair long when they toured the album in 1984, which along with the change in sound further alienated their hardcore skinhead fanbase.

In 1978, Black Flag guitarist and cofounder Greg Ginn converted his ham radio business Solid State Transmitters to SST Records to release the band's first EP Nervous Breakdown.

"[5][6] Following the release of Damaged, Black Flag absorbed a wider range of influences from the more experimental hardcore of Flipper, Void, and Fang.

[8] Music journalist Andrew Earles believes the band was influenced by the tiny but growing doom metal scene led by Saint Vitus (who released via SST).

[12] The disciplined group rehearsed obsessively, but there was little friendship between members: vocalist Henry Rollins was introverted and Ginn cold and demanding.

[17] The band explored new sounds on these tracks, which tended to feature a riff-heavy heavy-metal edge and noisy, energetic free guitar soloing from Ginn.

The first half features five tracks that are in the same style that the band originated on their previous album Damaged and closes with a noisy freak-out, "The Swinging Man".

[42] My War polarized Black Flag fans; it alienated those who wanted the band to stay true to its simple hardcore roots[7] and who were put off by the length of the songs, the riff-heaviness, and the solos—elements widely thought of as un-punk.

The ideology of many fans and critics demanded that hardcore punk bands remain true to the genre's roots, with short, fast songs, typically lacking solos.

[5][47] The muffled sound of the album's production has attracted criticism; Stevie Chick disparaged the lack of character in Ginn's bass-playing on "My War" when compared to the 1982 demo of the same song with Dukowski on bass.

[25] Michael Azerrad praised the strength of the material while denigrating the "frustrating lack of ensemble feel" as the album was recorded without a full lineup.

[48] John Dougan at AllMusic called the A-side of the album "quite good", but described the B-side as "self-indulgence masquerading as inspiration and about as much fun as wading through a tar pit".

[50] Mudhoney guitarist Steve Turner has said of the album's impact on grunge, "I swear, that record instantly made the Melvins slow down to a crawl.