Canadian band formed in Toronto, Ontario in 2004, blending hardcore punk with heavy metal.

Formed by singer Liam Cormier, guitarist Scott Middleton, bassist Andrew McCracken, and drummer Joel Bath, the band released a demo in early 2005, after which Bath was replaced by Mike Peters. Signing to local heavy metal label Distort Entertainment, they released their debut album, Birthing The Giant, in 2006. McCracken left and was briefly replaced by Jason Bailey. Middleton played both guitar and bass on 2008's Hail Destroyer, after which Jaye R. Schwarzer became the band's bassist. Bears, Mayors, Scraps & Bones followed in 2010, and Dead Set On Living in 2012. In 2011 Cancer Bats began performing sets of Black Sabbath covers under the name Bat Sabbath, and released the EP Bastards Of Reality in 2013.

Cancer Bats moved to another Toronto label, New Damage Records, for 2015's Searching for Zero. 2018's The Spark That Moves was co-released by New Damage and the band's own imprint, Bat Skull Records. During the COVID-19 pandemic, the band released a pair of acoustic EPs titled You'll Never Break Us: Separation Sessions.

Founding guitarist Scott Middleton left the band in 2021. Schwarzer played both guitar and bass on 2022's Psychic Jail Break and the Bat Sabbath live EP Masters Of Duality, both released on Bat Skull. Jackson Landry then joined as the band's new guitarist.