One of the Disney theme parks’ longest-tenured leaders, Dick Nunis, died Tuesday at the age of 91. 

Nunis’ work with Disney began before Disneyland’s July 17, 1955, opening, when he took a summer job after hearing about the park through his USC football teammate, Ron Miller — Walt Disney’s son-in-law. 

From his first job helping to train Disneyland employees, Nunis climbed the ladder to attractions supervisor of Adventureland to director of park operations to, by 1971, executive vice president of both Disneyland and Walt Disney World, a project he helped develop. 

He became president of what was then called the Outdoor Recreation Division of Walt Disney Productions in 1980 and retired in May 1999 as chairman of Walt Disney Attractions.

“Today, we mourn the passing of Dick Nunis, a true Disney Legend whose contributions to The Walt Disney Company have touched the lives of millions of people all over the world,” Walt Disney Company CEO Bob Iger said in a statement. “What started as a summer job training future Disneyland employees would ultimately become a storied 44-year career at Disney. Dick took the values and philosophies he learned directly from Walt and incorporated them into everything he did at Disney. We are grateful for his many achievements and we extend our deepest sympathies to his family and loved ones.”

Disney Experiences chairman Josh D’Amaro said in another statement, “On behalf of every Cast Member, Crew Member, Imagineer and employee of Disney Experiences, I want to express my gratitude to Disney Legend Dick Nunis and my condolences to his family following the sad news of his passing. Dick’s impact on our theme parks business is everlasting. Along with our founder, Walt Disney, Dick helped shape our business, create happiness for millions of families around the world and set a standard that an entire industry must now live up to.”

Nunis had released his memoir, “Walt’s Apprentice: Keeping the Disney Dream Alive,” last year.

 The Disney History Institute podcast also did an eight-part series on Nunis and his career up until the late 1960s, detailing some of the operational innovations he began and his no-nonsense management style. You can listen to the first episode here.