SUSSEX, THOMAS RADCLYFFE [or RATCLYFFE], 3RD EARL OF (c. 1525-1583), lord-lieutenant of Ireland, eldest son of Henry, 2nd earl of Sussex (see SUSSEX, EARLS OF), by his first wife, Elizabeth, daughter of Thomas Howard, 2nd duke of Nor folk, was born about 1525, and after his father's succession to the earldom in 1542 was styled Viscount Fitzwalter. After serving in the army abroad, he was employed in 1551 in negotiating a mar riage between Edward VI. and a daughter of Henry II., king of France. His prominence in the kingdom was shown by his inclu sion among the signatories to the letters patent of June 16, 1553, settling the crown on Lady Jane Grey; but he nevertheless won favour with Queen Mary, who employed him in arranging her marriage with Philip of Spain, and who raised him to the peerage as Baron Fitzwalter in August 1553. In April 1556, Fitzwalter was appointed lord deputy of Ireland. The measures enjoined upon Fitzwalter by the government in London comprised the reversal of the partial attempts that had been made during the short reign of Edward VI. to promote Protestantism in Ireland, and the "plantation" by English settlers of that part of the country then known as Offaly and Leix. But Fitzwalter first of all found it necessary to make an expedition into Ulster. Having defeated O'Neill and his allies the MacDonnells, the lord deputy, who by the death of his father in February 1557 became earl of Sussex, returned to Dublin, where he summoned a parliament in June of that year. Sussex then took the field against Donough O'Conor, whom he failed to capture, and afterwards against Shane O'Neill, whose lands in Tyrone he ravaged, restoring to their nominal rights the earl of Tyrone and his reputed son Matthew O'Neill, baron of Dungannon. (See O'NEILL.) In June of the following year Sussex turned his attention to the west, where the head of the O'Briens had ousted his nephew Conor O'Brien, earl of Thomond, from his possessions, and re fused to pay allegiance to the Crown ; he forced Limerick to open its gates to him, restored Thomond, and proclaimed The O'Brien a traitor. He took part in the ceremonial of Queen Elizabeth's coronation in January 1559; and in the following July he re turned to Ireland with a fresh commission, now as lord lieutenant, from the new queen, whose policy required him to come to terms if possible with the troublesome leaders of the O'Neills and the MacDonnells. Sussex was recalled, at his own request, in
His government of Ireland had not, however, been without fruit. Sussex was the first representative of the English Crown who enforced authority to any considerable extent beyond the limits of the Pale.
On his return to England, Sussex immediately threw himself into opposition to the earl of Leicester. In 1566 and the follow ing year Elizabeth employed him in negotiations for a marriage with the archduke Charles. When this project fell to the ground Sussex returned from Vienna to London in March 1568, and in July he was appointed lord president of the north, in which office he had to deal with the rebellion of the earls of Northumberland and Westmorland in 1569. In 1570 he laid waste the border, invaded Scotland, and raided the country round Dumfries, reduc ing the rebel leaders to complete submission. In July 1572 Sussex became lord chamberlain, and he was henceforth in frequent attendance on Queen Elizabeth, both in her progresses through the country and at court, until his death on June 9, 1583.
The earl of Sussex was a patron of literature and of the drama. He was twice married : first to Elizabeth, daughter of Thomas Wriothesley, earl of Southampton; and secondly to Frances, daughter of Sir William Sidney. His second wife was the foundress of Sidney Sussex College at Cambridge, which she endowed by her will. The earl left no children, and at his death his titles passed to his brother Henry.
See P. F. Tytler, England under the Reigns of Edward VI. and Mary (2 vols., 1839) ; Richard Bagwell, Ireland under the Tudors (3 vols., 1885-90) ; Calendar of the Carew MSS.; John Stow, Annales (1631) ; Charles Henry Cooper, Athenae cantabrigienses, vol. i. (Cambridge, 1858), containing a biography of the earl of Sussex ; John Strype, Ecclesiastical Memorials (Oxford, 1822) ; Sir Cuthbert Sharpe, Me morials of the Rebellion of 1569 (1840) ; John Nichols, Progresses and Public Processions of Queen Elizabeth (3 vols., 1823) ; Sir Wil liam Dugdale, The Baronage of England (1675).