The Weather Underground was a radical left wing militant organization first active in 1969, founded on the Ann Arbor campus of the University of Michigan. Originally known as the Weathermen, the group was organized as a faction of Students for a Democratic Society (SDS) national leadership. Officially known as the Weather Underground Organization (WUO) beginning in 1970, the group's express political goal was to create a revolutionary party to overthrow American imperialism.
The Weather Underground organized collectives around the United States in an attempt "to challenge the state directly in solidarity with Third World liberation movements, particularly the Black Power movement here and the Vietnamese in Southeast Asia." Collectives organized the white working class against imperialism by holding militant demonstrations and engaging in small scale property damage.
The FBI described the WUO as a domestic terrorist group, with revolutionary positions characterized by black power and opposition to the Vietnam War. The WUO took part in domestic attacks such as the jailbreak of Timothy Leary in 1970. The "Days of Rage" was the WUO's first riot in October 1969 in Chicago, timed to coincide with the trial of the Chicago Seven. In 1970, the group issued a "Declaration of a State of War" against the United States government under the name "Weather Underground Organization".
