Daniel M. Rooney was born on July 20, 1932 in Pittsburgh, Pennsylvania and he is the owner and chairman of the Pittsburgh Steelers and is also the United States Ambassador to Ireland.

He is the son of Steelers founder and former owner Art Rooney. Rooney was elected to the Pro Football Hall of Fame in 2000 for his great success as an owner. Rooney is also credited with the "Rooney Rule," which requires every NFL team with a head coaching and general manager vacancy to interview at least one minority candidate before making a final hiring decision. Rooney was appointed team president in 1975 of the Steelers organization and was given an enormous amount of power in the organization by his father.

Rooney is also the co-founder of the Ireland-related fundraising organization, The Ireland Funds.

Dan Rooney is a graduate of Duquesne University and majored in accounting. He has been involved with the Steelers since 1960 working under his father as the director of personnel.

While Rooney for the most part has avoided the spotlight, behind the scenes he has been a very active NFL owner. Rooney was a key contributor in helping the negotiations for the collective bargaining agreement of 1982, which helped to end a player’s strike that lasted half of the season.

Rooney is also one of the designers of the salary cap, which was implemented in 1993. He is also a Founding Chairman of The Mentoring Partnership of Southwestern Pennsylvania.

In 2008, Rooney became an honorary Commander of the British Empire. In 2009, he won the Jack Horrigan Memorial Award, presented by the Professional Football Writers of America to a professional football official or player "for his or her professionalism in helping football writers do their job".

During his tenure with the Steelers, Rooney has implemented a philosophy and management style that gives priority to open, practical and well-organized management. The results have been indisputable.  Since 1972, the Steelers have been the AFC Central Division champions 14 times and the AFC champions seven times, and have gone to win the Super Bowl six times. Rooney became outright owner of the team in 1988, following the death of Art Rooney, his father. Rooney has somewhat limited his control of the franchise since 2003, giving more of the power to his son Art Rooney II.

In November of 2008, Rooney's four brothers signed papers transferring the majority of the Steelers ownership to Rooney and his son, Art Rooney II, who is currently the team president. The complicated sale has been ongoing for nearly a year.

The sale allows Dan Rooney, now the U.S. ambassador to Ireland, and Art II to control 30 percent of the team's shares, which is required under NFL rules in order to be considered a principal owner of a team.

Rooney and his son are taking on about $250 million in debt to complete the takeover, and are using their shares as collateral for a loan arranged by PNC Bank.

Previously, the five sons of Steelers founder Art Rooney Sr., Dan, Pat, John, Art Jr. and Tim, each owned a 16 percent stake of the Steelers franchise.

Tim and Pat Rooney are selling their entire 16 percent stakes, while Art Jr. and John Rooney are selling about half of their shares in the deal. Tim and Pat Rooney are in charge of the family's racetrack business, which involves legal gambling operations, which are not allowed by NFL rules for any team owner.

Some of the 20 percent share previously held by the McGinley family of Pittsburgh also will be sold to Dan Rooney and his son. The late John "Jack" McGinley helped Art Rooney Sr. reacquire the Steelers in 1941, after Rooney briefly sold the team and bought into the Philadelphia Eagles.

To help them complete the transaction, Dan Rooney and Art Rooney II added additional investors, including movie producer Thomas Tull and James Haslam III, who is the president of the nation wide truck-stop organization “Pilot”, and the Paul family of Pittsburgh.

On March 17, 2009, President Obama announced he had nominated Rooney to become the next US ambassador to Ireland, citing the owner's longstanding support for Irish-American charitable causes.

Secretary of State Hillary Rodham Clinton swore him in as the new ambassador to Ireland on July 1, 2009. Ambassador Rooney presented his credentials to Irish President Mary McAleese on July 3, before making his first official speaking engagement at a lunch hosted by the American Chamber of Commerce in Ireland.

Although he has largely done so since becoming Steelers team president six years ago, Art Rooney II is currently running the Steelers organization with his father in Ireland.

During the 2008 United States Presidential campaign, Rooney publicly presented Democratic nominee, Barack Obama, with his own personalized Pittsburgh Steelers jersey while at a campaign rally.

This act enraged many Steelers fans that then saturated the conservative leaning Pittsburgh Tribune Review editorial board with letters of their disgust on October 31, 2008. Many of these Steelers fans made it known to the paper that politics has no place in the world of sports.

Other fans made it known that Rooney must understand that the Pittsburgh Steelers franchise represents the entire city of Pittsburgh and not just his own personal beliefs.

Even though Rooney previously declared himself a life-long Republican, many people in the media have described him a "Republican In Name Only" (RINO) for many years because he has supported tax increases on Pittsburgh residents to pay for Heinz Field, an amphitheatre, and a future subway service. Some residents have gone as far to state that because of these advocated tax increases; Rooney should not be publically endorsing any Presidential or political candidate.

Rooney publically endorsed Barack Obama for president, stating, "When I think of Barack Obama’s America I have great hope. I support his candidacy and look forward to his Presidency."

This did not go over well with the majority of Steelers fans who, though mostly middle class, are staunch conservatives and proud republicans.

Letters from lifelong Steelers fans who were extremely upset sent the following:

  "Shame on you! I was born in Pittsburgh and raised in McKeesport. My father was a Steeler fan from the word 'go' and raised me the same. My father was, as I am, a conservative Republican, as, I might add, are a few million other Steeler fans. I cannot speak for them, but I will never watch another Steeler game!!... I pay $250 to Direct TV so that I can get every game, every week, and have for years. I will have a bonfire of all my Steeler possessions and request that my 18-year-old grandson do likewise. "I will consider Oct. 27 the day something dear to me died."

"Dan Rooney is no different than anyone else and he's entitled to support the candidate of his choice, but he's not entitled to drape a Steeler shirt across Barack Obama. The impression is that we, the Steeler Nation, support Barack Obama and let me tell you, there are many of us who don't.”

"I was shocked. I grew up in Oakland and I love the Steelers, and this is not going to change my opinion of them. But now, I really don't care if Dan keeps the team. He doesn't deserve it, and his father would be spinning in his grave."