Calixa Lavallée (December 28, 1842 – January 21, 1891) was a French-Canadian-American musician and Union Army band musician during the American Civil War. He is best known for composing the music for "O Canada," which officially became the national anthem of Canada in 1980, after a vote in the Senate and the House of Commons. The same 1980 Act of Parliament also changed some of the English lyrics. A slight alteration to the English lyrics was made again in 2018. The original French lyrics and the music, however, have remained unchanged since 1880.