Dan Rooney accepts the Lombardi Trophy from NFL Commissioner Roger Goodell in 2009 after the Steelers beat the Cardinals in Super Bowl XLIII. (Al Bello/Getty Images)

Pittsburgh Steelers chairman Dan Rooney died Thursday, the team confirmed on social media. He was 84.

The team did not specify the cause of death.

Rooney grew up with the team after his father Art Rooney Sr. founded it in 1933, a year after Dan Rooney was born. The younger Rooney succeeded his father as the president of the organization in the ’70s but had already been playing a large role in guiding the team.

With him at the helm, the Steelers won four Super Bowls in six years, beginning with Super Bowl IX in 1975. The win came after Rooney influenced the Steelers’ decisions during the 1974 NFL draft, where the team picked up eventual Hall of Famers Lynn Swann, Jack Lambert, John Stallworth and Mike Webster.

With Rooney as president, the Steelers would go on to win Super Bowls X, XIII and XIV.

Rooney’s most important win, however, might have been off the field with the introduction of what became known as the “Rooney Rule,” which provides a platform on which minority coaches can their chance to coach in the NFL. Now employed by all the league’s franchises, the Rooney Rule requires teams to interview at least one minority coach when filling a head coaching vacancy.

In 2007, Rooney and his son Art II, who succeeded his father as team president in 2002 as Rooney stepped into his chairman role, hired Mike Tomlin, the team’s first black head coach.

“[Rooney] was like a father, a friend, a mentor, a boss who inspired others around him. He was a people person and he never forgot where he came from,” former coach Bill Cowher told the Pittsburgh Post-Gazette. “He epitomized Pittsburgh — hard working, humble, no-nonsense, tell it the way it is and never forget where he came from. That’s him, that’s Pittsburgh.”

The Steelers’ star wide receiver Antonio Brown also paid tribute to the Rooney on Thursday, as did quarterback Ben Roethlisberger. Both credited Rooney with allowing them to flourish as Steelers.

Rooney would go on to represent more than Pittsburgh in 2009 when former president Barack Obama nominated him to become the U.S. ambassador to Ireland. Rooney excitedly took on the new role, which he served in for more than three years, before returning to Pittsburgh.

Obama called Rooney “a great friend” and “a championship-caliber good man” in a statement following Rooney’s death Thursday.

“I knew he’d do a wonderful job when I named him as our United States Ambassador to Ireland, but naturally, he surpassed my high expectations, and I know the people of Ireland think fondly of him today,” he continued.

Irish President Michael D. Higgins proved Obama correct, noting he remembers Rooney and his family with “fondness” during Rooney’s time as ambassador.

“[He was] deeply committed to Ireland and the Irish people,” Higgins said in a statement. “He was always conscious of his Irish roots.”

Higgins added: “All of those who met him were quick to realize his love for his native Pittsburgh and for the game of American football.”

Indeed, Rooney’s mark on football earned him a spot in the Pro Hall of Fame in 2000. During his speech he credited his father for his success.

“It is special to join him here,” Rooney said of his dad during his acceptance speech in Canton (via the Post-Gazette). “He gave me the understanding of what the league meant. He gave me the commitment to do everything possible to keep it strong and viable.”

NFL Commissioner Roger Goodell lauded Rooney’s contributions to the game Thursday.

“Few men have contributed as much to the National Football League as Dan Rooney,” Goodell said in a statement posted to social media. “He is one of the finest men in the history of our game it was a privilege to work alongside him for so many years.”

He continued: “Dan’s friendship and counsel were both inspiring and irreplaceable. My heart goes out to [Rooney’s wife] Patricia, Art and the entire Rooney family on the loss of this extraordinary man.”

Rooney is survived by his wife, with whom he had nine children, including Art II.