Matthew 'Dutch' Rooney - grandson of Pittsburgh Steelers founder Art Rooney - has been found dead at his East Hampton home on August 15. He was 51 years old.

The cause of death has not been revealed, leaving questions in both the football world and New York's cultural circles where Rooney was a familiar figure. 

A member of one of America's most powerful sports dynasties, he carved out his own identity as a writer, patron of the arts, and presence at the ballet and opera.

'The Rooney Family is mourning the loss of Matthew,' the Steelers said in a statement confirming his death.

Property records obtained by Daily Mail show Rooney had purchased the East Hampton home in 2020. The white clapboard house is valued at $3.48 million.

The four-bedroom, five-bathroom property spans 2,813 square feet and features a landscaped garden, outdoor pool, with a modern farmhouse design.

Born in Meadowbrook, Pennsylvania, Rooney was the son of JoAnn Wallace Rooney and John J. Rooney, who once owned a 16 per cent stake in the Steelers before selling most of it in 2009.

He earned a degree from New York University and a master's at Columbia before splitting his time between New York and Los Angeles. 

In later years he made his homes in Brooklyn Heights, East Hampton, and West Palm Beach.

His obituary described him as 'a writer and artist, a lover of literature and passionate about ballet and opera,' noting that his 'wit, charm and love of fashion made him one of life's last true Dandies and an authentic Bon Vivant.'

Rooney didn't just attend performances - he supported them. He served as vice chair of the New York City Ballet's donor circle and sat on the board of the Metropolitan Opera.

Fashion designer Joshua Kamei also remembered his impact beyond the stage: 'I was saddened to hear about the passing of Matthew Rooney. I didn't know him well, but he was always a kind, familiar face at the ballet - someone who had a special way of making others feel welcome and celebrated.'

He is survived by his mother, four siblings, 15 nieces and nephews and 18 great-nieces and nephews.

A funeral mass and private burial will take place in Pennsylvania on August 21.

The Rooney family's ties to football stretch back to 1933, when Art Rooney Sr., nicknamed 'The Chief' founded the Steelers. He purchased the team for just $2,500.

He led the team until his death in 1988, passing the reins to his son Dan, who remained president until 2002.

Today, the storied franchise is run by Matthew's cousin, Art Rooney II, who continues the family's NFL legacy.

The dynasty also links Matthew to Hollywood. His relatives include actresses Rooney Mara and Kate Mara, whose father descends from New York Giants founder Timothy Mara - and whose mother is part of the Rooney family. 

The famous sisters have often spoken about growing up at the intersection of football royalty and the entertainment industry - a family tree that connects two of the NFL’s most iconic franchises with two of Hollywood’s most recognizable faces.