PRENDERGAST or PENDERGRASS, Sir THOMAS (1660?–1709), son of Thomas Prendergast, of an ancient family resident at Newcastle, co. Tipperary, by his wife Eleanor, daughter of David Condon, was born at Croane, probably about 1660. His family had suffered much at the hands of Cromwell, and Sir Thomas was subsequently described by Swift as the son of a cottager who narrowly escaped the gallows for stealing cows. Nothing is known of his early life beyond the fact that he was a staunch Roman catholic and a Jacobite, who stood high in the estimation of his friends as a man of honour and ability.
In January 1696 Sir George Barclay [q. v.] landed at Romney in possession of a definite scheme for the assassination of William III, and on Thursday, 13 Feb., Prendergast was summoned from Hampshire by George Porter [q. v.], Barclay's chief confederate, to lend his aid upon the following Saturday, when it was resolved to stop the king's coach at Turnham Green. The confederates numbered about forty, and one of them, named Fisher, had already given information respecting the conspiracy; but the king had paid no attention to his statement, thinking that it was too indefinite, and was moreover part of a settled policy to try and intimidate him. On Friday night Prendergast went to the Earl of Portland at Whitehall, independently confirmed all that Fisher had said, and gave so clear an account of the project as to convince William of its reality. The spies whom the conspirators kept at Kensington reported next morning that the king did not intend to drive to Richmond that day. Barclay's followers were not discouraged, for no arrests were made, and the accomplishment of the design was postponed until the following Saturday. Before that date a third informer, De la Rue, had presented himself at the palace; but William was specially desirous to get a confession from Prendergast, of whose probity he had been convinced. Accordingly on the night of Friday, 21 Feb., Prendergast was with due precaution summoned to the royal closet at Kensington; he there repeated his story to the king, in the presence of Cutts and Portland, and, after much entreaty, wrote down the names of the chief conspirators. The next day he attended the rendezvous of his associates at the lodgings of his friend, Captain Porter. The latter entrusted to him a musquetoon loaded with eight balls, and he was detailed with seven others to do the deed while the remainder kept the guards in play. But news received from Kensington caused the conspirators hastily to disperse, and in a few hours' time most of the leaders were in custody. Prendergast himself was not arrested until 29 Feb. He had obtained the royal word that he should not be a witness without his own consent, and he was determined not to be a witness unless he were assured of the safety of Porter, to whom he was under heavy obligation. His scruples were removed by Porter himself turning king's evidence, and he finally gave evidence against all the chief conspirators. His testimony carried greater weight than that of any of the other informers, and was material in procuring the conviction of Charnock, King, Keyes, Friend, and Parkyns. He was released in April, and soon received some signal marks of royal favour. On 5 May he received 3,000l. from the treasury, and a grant of land worth 500l. a year out of the forfeited estate of the Earl of Barrymore (Lodge, Irish Peerage, i. 294). He had several audiences with the king, by whom he was on 3 June 1699 created a baronet, and his estate was untouched by the Resumption Bill of 1700. He entered the army, and in June 1707 was created a lieutenant-colonel of the 5th regiment of foot, in succession to Lord Orrery. In the following April his regiment was ordered to Holland, and he was subsequently quartered at Oudenarde. He was promoted brigadier-general on 1 Jan. 1709, took a prominent part in the battle of Malplaquet on 11 Sept. 1709, and was mortally wounded while bravely leading his regiment to the assault of the French troops entrenched in the wood of Blaregnies. His death was recorded in the brief French despatch as that of ‘le brigadier Pindergratte’ (Mémoires Milit. relatifs à la succession d'Espagne 1855, ix. 370).
Prendergast married, in 1697, Penelope, only daughter of Henry Cadogan, and sister of William, first earl Cadogan [q. v.] This match, in conjunction with the favour of William III, enabled him to lay the fortunes of his family upon a sure foundation. He became in 1703 M.P. for Monaghan, and in the same year he repurchased Mullough and Croane from the commissioners of forfeited estates. He was succeeded in the baronetcy by his eldest son, Thomas, who adopted the protestant religion, became M.P. for Chichester and Clonmel, and was appointed postmaster-general of Ireland. His anti-clerical propensities made him an object of special detestation to Dean Swift, who wrote of him in 1733 as ‘Noisy Tom,’ and ‘spawn of him who shamed our isle, traitor, assassin, and informer vile’ (cf. an ironical Full and True Vindication of Sir T. P., by a member of the House of Commons). Swift attacked