English politician, son of Thomas Thurloe, rector of Abbots Roding in Essex; baptized on the 12th of June 1616. He studied law, entered the service of Oliver St. John, through whose interest he was appointed a secretary to the parliamentary commissioners at Uxbridge in January 1645. He was admitted to Lincolns Inn in 1647, and in March 1648 he received the appointment of receiver of the cursitors fines, worth £350 a year. He took no part in the subsequent historical events or in the kings death. In March 1651 he attended St. John and Sir Walter Strickland as secretary in their mission to Holland, and on the 29th of March 1652 he was appointed secretary to the council of state, being apparently also elected a member thereof about the same time. His duties included the control of the intelligence department and of the posts, and his perfect system of collecting information and success in discovering the plans of the enemies of the administration astonished his contemporaries. By his means, it was said, Cromwell carried the secrets of all the princes of Europe at his girdle. On the 10th of February 1654 he was made a bencher of Lincolns Inn. In the parliaments of 1654 and of 1656 he represented Ely; he was appointed a member of Cromwells second council in 1657; was elected a governor of the Charterhouse in the same year; and in 1658 became chancellor of Glasgow University. Thurloe was attached to Cromwell as a man and admired him as a ruler, and Cromwell probably placed more confidence in the secretary than in any one of those who surrounded him. Thurloe, however, by no means directed Cromwells policy. He was in favour of the protectors assumption of the royal title, and was opposed to the military party who obtained the ascendancy. After Olivers death he supported Richard Cromwells succession and took a prominent part in the administration, sitting in the parliament of January 1659 as member for Cambridge University. Attacked by the republicans on the ground of arbitrary imprisonments and transportations during the Protectorate, he succeeded in vindicating his conduct; but the breach between the army and the parliament, and the ascendancy obtained by the former, caused his own as well as Richards downfall. Nevertheless, being indispensable, he was reappointed secretary of state on the 27th of February 1660. He appears to have steadily resisted the Restoration, and his promises of support to Hyde in April inspired little confidence. On the 15th of May 1660 he was arrested on the charge of high treason, but was set free on the 29th of June, subject to the obligation of attending the secretaries of state for the service of the state whenever they should require. He subsequently wrote several papers on the subject of foreign affairs for Clarendons information. He died on the 21st of February 1668 at his chambers in Lincolns Inn, and is buried under the chapel there. Thurloe was twice married, and by his second wife Anne, daughter of Sir John Lytcote of East Moulsey in Surrey, he had four sons and two daughters.
His extensive correspondence, the originals of which are in the Bodleian Library at Oxford and the British Museum (Add. MSS. 4156, 4157, 4158), is one of the chief sources of information for the period. A portion was published with a memoir by T. Birch in 1742, and other correspondence is printed in R. Vaughans Protectorate of Oliver Cromwell (1836). See also Die Politik des Protectors Oliver Cromwell in der Auffassung und Thatigkeit des Staatssecretärs John Thurloe, by Sigismund, Freiherr von Bishoffshausen (1899); Eng. Hist. Review, xiii. 527 (Thurloe and the post office); Notes and Queries, 11th series, vol. viii. p. 83 (account of his death); A Letter to a Friend on the Publication of Thurloes State Papers (1742); Clarendons History of the Rebellion; Gardiners History of the Commonwealth.