Sir Thomas FitzGerald of Laccagh (c.1458-1487), younger son of the 7th Earl of Kildare, was Lord Chancellor of Ireland under Richard III and Henry VII, but rebelled against Henry and was killed at the Battle of Stoke.
He was born about 1458, second son of Thomas FitzGerald, 7th Earl of Kildare and Joan FitzGerald, daughter of James FitzGerald, 6th Earl of Desmond. He married Elizabeth Preston, daughter of Robert Preston, 1st Viscount Gormanston and Janet Molyneux. Through his eldest daughter Margaret, who married Garrett Wellesley, he was an ancestor of the Duke of Wellington. He resided at Laccagh in County Kildare, and despite his rebellion against the Crown his descendants retained his estates.
He became Lord Chancellor of Ireland in 1484. After the downfall of the Yorkist dynasty the new King Henry VII confirmed him in office, but his loyalty to the new regime was deeply suspect. The Anglo-Irish nobility were in general strongly Yorkist, while the Fitzgeralds of Kildare were regarded as being willing to back whichever rival dynasty would advance their own power: Henry VII is said to have remarked that they would crown an ape to secure their own position. Thomas's father, and his eldest brother Gerald, "the Great Earl", had reached a position of almost absolute power in Ireland.
In 1487 the impostor Lambert Simnel, who claimed to be Edward Plantagenet, 17th Earl of Warwick, rightful heir of the House of York, appeared in Ireland. Thomas and his brother Gerald, 8th Earl of Kildare, were among his strongest supporters and were present at his coronation in Christchurch Cathedral, Dublin. Thomas resigned the Chancellorship and recruited a force of some 4500 soldiers, including both Old Irish and Anglo-Irish, to supplement a troop of Continental mercenaries sent by the real Warwick's aunt, Margaret of York. He led his troops to England; but the rebellion was crushed at the Battle of Stoke, where Thomas was killed. His brother was more fortunate: Henry showed remarkable clemency to the surviving rebels, including Kildare, who received a royal pardon, and Simnel himself, who was given a job in the royal kitchens, and later promoted to the office of Falconer. The Fitzgeralds retained their predominance in Irish politics for another 50 years: another reported remark of King Henry VII was that if all Ireland could not rule them, then they must rule all Ireland. However his son Henry VIII came in time to take a very different view: by 1540 the Kildare Fitzgeralds had been crushed, although they later regained some of their power.