According to the Associated Press, the avid outdoorsman died Saturday in his home in Patagonia, Ariz. The cause of death is unknown.
Harrison's career began in earnest in 1971 with his first novel Wolf: A Fake Memoir. After a bit of a slump, he came across letters at his in-laws' home that inspired him to write the stories that would become Legends of the Fall. Jack Nicholson loaned him $15,000 to finish the work, which reinvigorated his career.
He wrote more than 30 books, and enjoyed hunting, fishing and food--once famously polishing off a 37-course lunch. Friends with members of the Hollywood elite including Jack Nicholson and Sean Connery, Harrison worked on scripts for films including Revenge with Kevin Costner and Wolf with Nicholson.
He was voted into the American Academy of Arts and Letters in 2007. His wife of more than 50 years, Linda King Harrison, died last year.