Crass were an English collective and punk rock band formed in 1977 which promoted anarchism as a political ideology, a way of life and a resistance movement. Crass popularised the anarcho-punk movement of the punk subculture, advocating direct action, animal rights and environmentalism. The band used and advocated a DIY punk ethic approach to its sound collages, leaflets, albums and films.
Crass spray-painted stencilled graffiti messages in the London Underground system and on advertising billboards, coordinated squats and organised political action. The band expressed its ideals by dressing in black, military-surplus-style clothing and using a stage backdrop amalgamating icons of perceived authority such as the Christian cross, the swastika, the Union Jack and the ouroboros.
The band was critical of punk subculture and youth culture in general. Crass promoted an anarchism which became more common in the punk-music scene. They are considered art punk in their use of tape collages, graphics, spoken word releases, poetry and improvisation.