Calixa Lavallée, (1842 - January 21, 1891), a French-Canadian musician, composed the music for the Canadian national anthem "O Canada".

He was born at Verchères, Quebec . He went to the U.S. in 1857 and lived in Rhode Island where he enlisted in the Northern army in the American Civil War.

During and after the war he moved between Canada and the United States and developed a career in music. He was also a director, conducting major orchestral and operatic productions in important concert halls like the Montreal Academy of Music in Montreal. He died in Boston. His remains were brought to Montreal in 1933.