The National Acadian Day is observed in Canada each year on August 15, celebrating the Assumption of Mary. It was during the first National Convention of the Acadians held at Memramcook, New Brunswick, in 1881 that the Acadian leaders received the mandate to set the date of this celebration.

The choice of the date was the object of a debate at the convention between those wishing for Acadians to celebrate June 24, Saint-Jean-Baptiste Day, and National Day of French Canadians since 1834 and National Holiday of Quebec since 1977, and others wishing the celebration to occur on August 15.