Régine Chassagne was born in Montreal, Quebec, Canada, and grew up in St-Lambert, a suburb south of Montreal. Her parents, who were of Haitian origin, emigrated from Haiti during the dictatorship of François Duvalier, which is alluded to in the Arcade Fire song "Haiti", in which she sings, Mes cousins jamais nés hantent les nuits de Duvalier ("My unborn cousins haunt Duvalier's nights"). The line is in reference to the relatives who were killed during the Jérémie Vespers massacre.
Chassagne attended the prestigious Collège Jean-de-Brébeuf before earning a B.A. in communication studies at Concordia University in 1998, and went on to study jazz voice briefly at McGill University. She was singing jazz at an art opening at Concordia in 2000 when Win Butler met her and persuaded her to join his band; after line-up changes, only the two of them were left. They married in 2003 and had their first child, a son, on April 21, 2013.
Chassagne has also been involved with a medieval band called Les Jongleurs de la Mandragore, and a jazz band, Azúcar. She also wrote the music for the two-minute David Uloth sketch "The Shine", and contributed to the UNICEF benefit project as part of the North American Hallowe'en Prevention Initiative, performing the song "Do They Know It's Hallowe'en?" along with Win Butler.
^Hoard, Christian (March 10, 2005). "The Fire This Time". Rolling Stone (969). pp. 59–60. Posted in an abridged form at "The Fire This Time". rollingstone.com. February 24, 2005. Archived from the original on 2 October 2007. Retrieved 19 October 2007.