He had been diagnosed with brain cancer.
Castille was a world-reknowned musician, particularly popular in French-speaking areas, including provinces of Canada.
Castille began playing the fiddle as a teenager. His style, which blended traditional and contemporary sounds, was inspired by another Cajun fiddler, Harry Choates, whom Castille heard as a child.
Castille was at home playing Acadiana dance halls and festivals as well as national and international television and radio shows and at concerts around the world.
He was an ardent advocate of French immersion at local schools and promoted the Cajun culture and the French language across Louisiana and the United States.
Arrangements are pending.