Ulick succeeded his father to the headship of his clan, and held vast estates in County Galway. In March 1541 he wrote to Henry VIII, lamenting the degeneracy of his family, which had rebelled against England in the mid-14th century, and "which have been brought to Irish and disobedient rule by reason of marriage and with those Irish, sometime rebels, near adjoining to me," and placing himself and his estates in the king's hands. The same year he was present at Dublin, when an act was passed making Henry VIII King of Ireland. In 1543, in company with other Irish chiefs, he visited the King at Greenwich and made full submission in accordance with the King's policy of "surrender and regrant". He was confirmed in the captainship and rule of Clanricarde, and on 1 July 1543, he was created Earl of Clanricarde and Baron of Dunkellin in the peerage of Ireland. He was regranted the greater part of his former estates, with the addition of other lands. The grant of the English titles was conditional upon the abandonment of native titles, the adoptation of English customs and laws, the pledging of allegiance to the English crown, apostasy from the Roman Catholic Church, and conversion to the Anglican Church. In his review of the state of Ireland in 1553, Lord Chancellor Cusake stated "he making of McWilliam earl of Clanricarde made all the country during his time quiet and obedient." He did not live long to enjoy his new English dignities, but died shortly after returning to Ireland about March 1544. He is called by the annalist of Loch Cé "a haughty and proud lord," who reduced many under his yoke, and by the Four Masters "the most illustrious of the English in Connaught."
Marriages
Burke married three times, first to Grany or Grace, daughter of Mulrone O'Carroll, by whom he had Richard, who eventually succeeded him as Second Earl of Clanricarde. This marriage was the only one declared valid. He eventually divorced Grace and then married Honora, sister of Ulick de Burgh, but divorced her as well, marrying Maire Lynch, by whom he had John, who claimed the earldom in 1568. According to Burke's Peerage, he had several other sons, Thomas "the Athlete", shot in 1545, Redmond "of the Broom", died 1595, and Edmund, died 1597.
Legacy
As a result of his marriages and relationships there were a number of candidates contending for the titles of Clanricarde and Earl. The eventual successor was Ulick's eldest legitimate son, Richard Sassanach Burke, 2nd Earl of Clanricarde.