McCague became the first Monaghan man to serve as GAA president when he took over in 2000
Sean McCague, the GAA president who was at the helm when Rule 21 was removed, has died at the age of 77.
Monaghan native McCague served as the association's president between 2000 and 2003.
The most significant moment of his three-year term in office came in 2001 when the GAA voted to scrap Rule 21, which banned members of the British security forces playing gaelic games.
McCague also won three Ulster titles as manager of the Monaghan footballers.
The first of those titles, in 1979, was the county's first Ulster triumph in 41 years. McCague also led Monaghan to provincial success in 1985 and 1988, and won the National League in 1985.
After managing his club Scotstown and the county team, McCague chaired the GAA's Games Administration Committee and also held administrative roles for Monaghan GAA and the Ulster Council.
GAA president Larry McCarthy said: "On behalf of our members and the Association as a whole, I would like to offer my condolences to Sean's wife Bernie, and his daughters Paula, Nuala, Martha, Freda and Emma and also to his wide circle of friends and those who admired and respected him.
"Sean was an astute leader at a time when the organisation benefitted greatly from his wisdom, experience and undoubted influence.
"He served the Association at every level, from Scotstown up and he left an indelible mark on our games and the GAA as we know it today."
McCague succeeded Joe McDonagh as GAA president in 2000, becoming the first Monaghan man to take up the position.
In November 2001, McCague announced the GAA's decision to lift its controversial Rule 21 following a vote at a special congress in Dublin.
During his time as president, McCague was also instrumental in securing funding for the redevelopment of Croke Park.
In a statement, Monaghan GAA said: "It is with a heavy heart today we mark the sad passing of former Uachtarán Monaghan and Scotstown's Sean McCague.
"In his renowned GAA career Sean served as the 33th President of our association from 2000-2003 in which his legacy still remains and managed Monaghan Senior Football team to Ulster historical success in the 70s and 80's.
"Former Principle of Scoil Mhuire in Monaghan, Sean was always at the helm of our association both locally and nationally and will be sadly missed by all.
"Our thoughts and prayers are with Sean's family and friends."
