Dr. Mason's commitment to serving the community as a private citizen began in earnest as soon as he and his family moved to Biloxi in 1955.
He became a Scoutmaster, leading Troop 416 for 15 years, beginning in 1959. He also became a member of the PTA, a 33rd degree Mason at the local Masonic Lodge, and an Elk.
He also was one of the founders of the Zeta Mu Lambda alumni chapter of Alpha Phi Alpha fraternity, and served as a charter member of both the Beta Gamma Boule in Jackson, MS and Delta Omicron Boule of Sigma Psi Phi Fraternity.
His most notable contributions to the Mississippi Gulf Coast and the pivotal work to combat injustice during the Civil Rights Movement came through his fights for desegregation of public schools and hospitals, establishing voting rights, and most notably, staging non-violent demonstrations to challenge the segregation of beaches in Harrison County.
Dr. Mason served as founder and President of the Biloxi branch of the National Association for the Advancement of Colored People (NAACP), founding the chapter in 1960. He spearheaded the beach wade-ins in 1959, 1960, and 1963, often cited as the first concerted acts of civil disobedience undertaken in Mississippi during the Movement. The dangerous and divisive demonstrations, as well as a court case that challenged the long-held belief of white residents that the beach was their private property, culminated in a landmark ruling by the United States Supreme Court in 1968 that the beaches be open to all. To hear more of his account of the initial wade-ins, listen to his testimony here.
Alongside Medgar Evers and Dovie Hudson, Dr. Mason also served as lead plaintiff in the first school desegregation suit in Mississippi (on behalf of his son Gilbert Jr.) and, despite ongoing death threats and bomb scares as well as being subject to surveillance by the state-sanctioned Sovereignty Commission, resulted in the schools becoming equal access via court decree in August 1968.
Mason collaborated with other Mississippi NAACP activists, including Winston Hudson, Amzie Moore, Aaron Henry and Medgar Evers (becoming close friends with him and serving as a pallbearer after his tragic assassination).
He helped the NAACP join with CORE, SNCC and SCLC to form the Council of Federated Organizations (COFO). Mason played a role in COFO's massive black voter registration drive, the Freedom Summer of 1964. He served as a delegate to the Democratic National Convention in 1968, 1972, 1976, and 1988.
He continued as founding president of the Biloxi branch until 1997, serving as President emeritus until his death, and as state Vice President until retiring in 2003.