This article analyses the emergence of politically motivated acts of left-wing terrorism in Britain between 1967 and 1972. Through the case of the ‘Angry Brigade’, an ill-defined grouping which claimed responsibility for a number of attacks against property between 1970 and 1971, it analyses how protest and political violence emerged from discourses and events in the British New Left, the anti-war protest movements, the counterculture, and the underground press. Against common interpretations of ’68 as a watershed of naïve hopes that waned into inaction, this article identifies a consistency of political activity that developed beyond traditional party and class politics towards a more internationally aware and diverse network of struggles for civil equality. Among the shared political and cultural commitments of the counterculture, campaigns around squatting, women's liberation, or the necessity of ‘armed propaganda’ each became possible and at times overlapped. It analyses the group's development, actions, communications, as well as surrounding media discourses, subsequent police investigation, and the criminal trials of ten individuals for their involvement in the Angry Brigade. The article reappraises their overlooked historical significance among the wider countercultural militancy and discourses of political violence of the late 1960s to early 1970s.