Brittain was known by reputation as a kind, gentle man and was well liked by students and faculty. He was especially remembered for his dedication to the Georgia Tech Yellow Jackets football team, attending nearly every game including those taking place out-of-state. Outside of Georgia Tech, Brittain taught Sunday school classes and maintained active membership in a number of service organizations. Brittain retired from his position as president of Georgia Tech in 1944, after which he penned a history of the Institute entitled "The Story of Georgia Tech", completed in 1948. He died in 1953, survived by three children: McDonald, Marion Luther, Jr., and Ida, three grandsons, and a great-granddaughter. Flags at the university were flown at half-staff for a month in remembrance of Brittain, and classes were cancelled for the rest of the school week.