His elder brother, Theobald Butler, was the heir at the death of his father in 1285 but died childless in 1299, when he inherited the paternal estates and titles.
From August 1312 to June 1314, he was Justiciar of Ireland, heading the government of the island, and acting frequently in a judicial capacity by holding assizes.
During that time he organised a successful campaign to subdue the O'Byrne clan in Leinster and at a Michaelmas feast in Dublin in 1313 he created thirty new knights.
[1][2] In 1320 he was released by the Pope from a vow to make a pilgrimage to Santiago de Compostela and spent his remaining time in England, where in 1321 he was negotiating a marriage of his daughter Joan to a son of Roger Mortimer, settling lands in Ireland on the couple.
[1] On 13 September 1321 he died in London and the next month his body was buried in St. Mary's Collegiate Church at Gowran in Kilkenny,[1][2] where the Bishop of Ossory and the Prior of the Hospitallers had undertaken to supply four priests to pray for his soul and those of family members.