Robert Burton "Mack" McCormick (August 3, 1930 – November 18, 2015) was an influential American musicologist and folklorist, renowned for his extensive research into the history of the blues. Born in Pittsburgh, Pennsylvania, McCormick was raised in various states, including Alabama, Colorado, West Virginia, and Texas, due to his parents' divorce and his mother's work as a hospital technician.

McCormick's early exposure to jazz and swing music led him to work with musicians like Stan Kenton and Buddy Rich at a young age. He dropped out of high school and pursued various jobs, including as an electrician, cook, and taxi driver, which allowed him to immerse himself in the diverse musical culture of Houston, Texas. His fascination with blues music deepened as he began documenting and recording the lives of undocumented blues musicians across the United States.

In the late 1950s, McCormick played a crucial role in the rediscovery and recording of artists such as Mance Lipscomb, Robert Shaw, and Lightnin' Hopkins. He was instrumental in reviving Hopkins's career and recorded his "Autobiography in Blues" in 1959. McCormick's work extended to producing albums and writing liner notes that captured the rich musical traditions of Texas and the surrounding regions.

McCormick's research on the legendary blues musician Robert Johnson began in 1968 and culminated in the posthumous publication of "Biography of a Phantom" in 2023. His meticulous work uncovered new material, including previously unknown photographs and interviews with Johnson's relatives.

Despite his significant contributions to musicology, McCormick struggled with personal challenges, including bipolar disorder, which affected his ability to publish his findings during his lifetime. Nevertheless, his legacy endures through his extensive archives, which include sound recordings, unpublished manuscripts, and photographs, now housed at the Smithsonian Institution.

Mack McCormick passed away from esophageal cancer in Houston, Texas, at the age of 85, leaving behind a lasting impact on the study and preservation of American blues and folk music.