FitzMaurice, Thomas (1574–1630), 18th Lord Kerry and Baron Lixnaw , the eldest of the three sons and two daughters of Patrick FitzMaurice (qv) and his wife Joan, daughter of David, Lord Fermoy, followed his father into rebellion in 1598. Succeeding to the title on his father's death in August 1600, he sought the favour and protection of the lord president, Sir George Carew (qv), who required him to earn it by performing some service for the crown. FitzMaurice refused on the grounds that to do so would be contrary to his conscience and honour and some months later Sir Charles Wilmot (qv) laid siege to his sole remaining residence, the castle of Listowel. FitzMaurice was elsewhere, but when the castle was surrendered after three weeks his elder son Patrick, a child of five years, was taken and sent to the lord deputy in Dublin.
The loss of the castle and the provisions stored there left FitzMaurice and his companions, in Carew's words, ‘no better than wood kerne’ (C. Carew MSS, 1589–1600, 470), and he sued for mercy. This plea was rejected by Carew and in December 1600 the queen specifically excluded FitzMaurice from all pardons offered to the rebels. Although she moderated her position before long, and indicated that she was willing to offer him a pardon for his life only, FitzMaurice had already joined Tyrone (qv) and O'Donnell (qv) in the north and taken up a command in O'Donnell's army. Late in 1601 he returned to Munster with O'Donnell, who repaid his support by detailing a force to detour through Kerry and plunder his enemies.
FitzMaurice remained with O'Donnell and was present at the Irish defeat outside Kinsale (24 December 1601). In the ensuing reduction of Munster, his contingent of 200 foot and 20 horse were routed and his provisions taken by Captain Thomas Boyce at Ballingarry, near Listowel, early in 1603. FitzMaurice succeeded in evading capture until the war's end, when he petitioned the lord deputy for mercy. On the instructions of James I he was pardoned under the great seal and restored to his lands by new letters patent (performed 16 July 1604), on condition that he allowed his son and heir Patrick to be fostered with the earl of Thomond (qv), and brought up a protestant. Patrick's mother, FitzMaurice's first wife, Honora O'Brien, who had died in 1600, was Thomond's sister.
Thereafter, FitzMaurice was obedient to the crown, although he was not free from suspicion. In 1608 it was alleged that he had in readiness 400 or 500 men in armour, and that he was the most likely source of trouble in Munster. When parliament met in 1613 he took his place in the house of lords where his claim of precedence over Lords Slane and Courcy was decided in his favour. In 1618 a dispute arose between him and his protestant son Patrick, for whom he had failed to provide a promised marriage settlement. When Patrick complained to the English privy council, FitzMaurice was arrested and imprisoned in the Fleet for a short time before being released on condition that he fulfilled his obligation. He did not do so and the case dragged on fitfully in both England and Ireland. A determined attempt to resolve the dispute in 1626 came to nothing. In the meantime, FitzMaurice had suffered a further period of imprisonment after his arrest in 1624, at the instance of the earl of Cork (qv), on suspicion of treason. He had been released by 1626 but he continued to be classified by the administration as discontented and dangerous.
FitzMaurice died on 3 June 1630 at Drogheda and was buried at Cashel in the chapel and tomb of St Cormac. He was married secondly to Julia, daughter of Richard, Lord Power of Curraghmore, with whom he had five sons and three daughters.