Question: The San Quentin Six were six inmates at San Quentin State Prison in the U.S. state of California, they were accused of participating in an escape attempt, on which date, that left six people dead, including George Jackson, a co-founder of the Black Guerrilla Family?

Related documents: [0]  [DOC] The Black Guerilla Family, or BGF (also known as the Black Family or the Black Vanguard) is an African-American prison and street gang founded in 1966 by George Jackson and W.L. Nolen while they were incarcerated at San Quentin State Prison in Marin County, California. [END] 
[1]  [DOC] The San Quentin Six were six inmates at San Quentin State Prison in the U.S. state of California (Hugo Pinell, Willie Tate, Johnny Larry Spain, David Johnson, Fleeta Drumgo and Luis Talamantez), who were accused of participating in an August 21, 1971 escape attempt that left six people dead, including George Jackson, a co-founder of the Black Guerrilla Family. [END]  
Answer: August 21, 1971
August 21, 1971