Thomas Le Boteller, or Thomas Butler, nicknamed Thomas Bacach or Thomas the Lame (before 1386 – 1420), was the illegitimate son of the 3rd Earl of Ormond, and a leading political figure in early fifteenth century Ireland. He held the offices of Lord Chancellor of Ireland, Lord Deputy of Ireland and Prior of Kilmainham. In his own time he was a highly unpopular statesman, who was accused of treason. He is now chiefly remembered as a professional soldier, who was present at the Siege of Rouen in 1418-19, and fought in the sanguinary encounter known as the Battle of Bloody Bank near Dublin in 1402.
He was the son of James Butler, 3rd Earl of Ormond, by the Earl's unnamed mistress; he was not, as is sometimes said, the son of the Earl's first wife Anne Welles. His date of birth is uncertain, but since he saw combat in 1402, was Lord Deputy of Ireland in 1406 and Prior of Kilmainham by 1410, it must have been well before his first legitimate brother was born in 1392, and most likely before his father's first marriage in 1386. Thomas' nickname Bacach, "the lame" indicates that he was crippled, but this did not stop him from pursuing a highly successful military career. It is said that he had a son named John Beagh Botiller, who was born before 1420 and died in Kilkenny, County Kilkenny, although this cannot be verified with certainty.
He was Prior of the Order of the Knights Hospitaller at Kilmainham from sometime before 1410 until his death in 1420. He was made Lord Chancellor of Ireland in 1412 but due to the pressure of other duties he usually acted through his deputy, Robert Sutton. He was made Lord Deputy of Ireland in the absence of Thomas of Lancaster, Duke of Clarence in 1406, in which office he is said to have exercised great political influence. O'Flanagan states that Parliament threw out a Bill to regulate the Irish Church on le Botellers sole objection. Such conduct naturally led to complaints, and may explain the attack on him by his opponents in 1411-12.