John Sylvanus Thompson (8 March 1889 – 1963) was an American pianist, composer, and educator. He was born in Williamstown, Pennsylvania, to James C. Thompson, a merchant in a general store, and his Welsh wife, Emma J. Thompson (nee Hall). John had three younger siblings: Alma, born 1895, James Jr., born in 1900, and Frank, born in 1905. Thompson had a promising career as a pianist, performing in many cities in America. In July, 1909, Thompson applied for a passport in preparation for touring Europe as a concert pianist.