Hamer began civil rights activism in 1962, continuing until her health declined nine years later. She was known for her use of spiritual hymnals and quotes and her resilience in leading the civil rights movement for black women in Mississippi. She was extorted, threatened, harassed, shot at, and assaulted by racists, including members of the police, while trying to register for and exercise her right to vote. She later helped and encouraged thousands of African-Americans in Mississippi to become registered voters and helped hundreds of disenfranchised people in her area through her work in programs like the Freedom Farm Cooperative. She unsuccessfully ran for the U.S. Senate in 1964 and the Mississippi State Senate in 1971. In 1970, she led legal action against the government of Sunflower County, Mississippi for continued illegal segregation.