Michael Blake, who won an Oscar for penning the script of “Dances With Wolves,” has died, his manager and producing partner Daniel Ostroff has confirmed. He was 69.

According to Ostroff, Blake died peacefully in Tucson, Ariz., after battling a long illness.

Blake wrote the novel “Dances With Wolves” in 1988, before it was turned into an Oscar-winning feature. The book would go on to sell more than 3.5 million copies and be translated into 15 different languages.

The film came out in 1990, directed by and starring Kevin Costner, and was both a commercial and critical smash. Along with screenplay, it won six other Oscars, including best picture. The script also won the prize at the WGA Awards and the Golden Globes.

Costner later commissioned Blake to write two other screenplays — “The Mick” and “The One.” Before “Dances With Wolves,” the two worked together on “Stacy’s Knights” in 1983.

Blake most recently wrote a screenplay based on German novel “Winnetou” for Constantin Films in 2011.

Ostroff acquired film rights for the “Dances With Wolves” sequel “The Holy Road” last year. Matt Murphy is also developing “Dances With Wolves” for the stage.

Blake’s other novels include “Airman Mortensen,” “Indian Yell,” “Marching to Valhalla,” “Twelve The King,” and “Like A Running Dog.”

He is survived by his wife, Marianne, and their three children. His family requests that any donations made should be made to the International Society for the Protection of Mustangs and Broncos.