Dan Reeves won a Super Bowl as a player with the Dallas Cowboys but was best known for a long coaching career that included four more Super Bowl trips with the Denver Broncos and Atlanta Falcons.
He finished his coaching career with a 190-165-2 record.
Reeves stayed in Atlanta after retiring, most notably as an adviser to Georgia State when it started a football team that now competes in the Sun Belt Conference.
He was 77 years old at the time of his death.
Dan Reeves death: What is the cause of Dan Reeves’ death?
Reeves died of dementia complications, according to a statement given by his family through former Falcons media relations director Aaron Salkin.
He died “peacefully and surrounded by his beloved family at his home in Atlanta,” according to the statement.
“His legacy will live on through his numerous friends, players, fans, and the rest of the NFL community,” the family wrote.