Medgar Wiley Evers (; July 2, 1925 – June 12, 1963) was an American civil rights activist and the NAACP's first field secretary in Mississippi, who was murdered by Byron De La Beckwith. Evers, a decorated U.S. Army combat veteran who had served in World War II, was engaged in efforts to overturn segregation at the University of Mississippi, end the segregation of public facilities, and expand opportunities for African Americans including the enforcement of voting rights.

A college graduate, Evers became active in the Civil Rights Movement in the 1950s. Following the 1954 ruling of the United States Supreme Court in Brown v. Board of Education that segregated public schools were unconstitutional, Evers challenged the segregation of the state-supported public University of Mississippi, applying to law school there. He also worked for voting rights, economic opportunity, access to public facilities, and other changes in the segregated society. Evers was awarded the 1963 NAACP Spingarn Medal.

Evers was murdered in 1963 at his home in Jackson, Mississippi, now the Medgar and Myrlie Evers Home National Monument, by Byron De La Beckwith, a member of the White Citizens' Council in Jackson. This group was formed in 1954 in Mississippi to resist the integration of schools and civil rights activism. As a veteran, Evers was buried with full military honors at Arlington National Cemetery. His murder and the resulting trials inspired civil rights protests, and his life and death inspired numerous works of art, music, and film. Although all-white juries failed to reach verdicts in Beckwith's first two trials in the 1960s, he was convicted in 1994 based on new evidence.

Medgar's widow, Myrlie Evers, became a noted activist in her own right, serving as national chair of the NAACP. In 1969 his brother Charles became the first African American to be elected mayor of a Mississippi city in the post-Reconstruction era.