Dan Rooney lived a full life. He went about his business in a dignified, but genuine way, never meeting someone who couldn't be a friend or acquaintance. In owning the Pittsburgh Steelers, he was at the helm of one of the most successful and respected franchises, not just in the NFL, but in all of professional sports. Because of all of these factors and more, a profound sadness descended upon his city and his league when Rooney passed away on Thursday at the age of 84.

A football life

Rooney was born on July 20, 1932, mere months before the inception of the Pittsburgh Steelers.

The team was founded by his father, Art, and has been within the family ever since. Dan Rooney became the second president of the team in 1975, a role he served in until 2002. The results on the field speak for themselves: the team won six Super Bowls under his ownership and eight AFC Championships while becoming the flagship organization of the NFL.

His biggest impact on football may not have come through his team's success, though. He was the inspiration behind the "Rooney Rule," one of the most significant pieces of legislation in North American sports. It requires NFL teams to interview at least one minority for head coach and general manager openings. Interestingly, that could have been considered giving away secrets to success, as Mike Tomlin's tenure as head coach of the Pittsburgh Steelers has been nothing but a success.

Beyond the gridiron

Rooney wasn't just the owner of the Pittsburgh Steelers. He also was an ardent diplomat, campaigning for Barack Obama in 2008 even though he was a card carrying Republican. President Obama rewarded him, as he served as the ambassador to Ireland from July 2009 until December 2012. He also co-founded "The Ireland Funds," which raised money for all sorts of philanthropic causes having to do with Ireland and Irish ancestry, ranging from education to the arts.

Condolences poured in from across the NFL on Thursday. Local franchises, such as hockey's Penguins and baseball's Pirates mourned. Former Steelers cornerback Ike Taylor sent out a tweet with a picture of the two together. Cam Heyward did the same. Former Steelers coach Bill Cowher sent a heartfelt message out, while NFL commissioner Roger Goodell released a statement on the passing of Rooney, who is survived by his wife, nine children, and in a spiritual way, fans of one of the greatest sports teams in the entire world.