In the December following his return, Walsingham was appointed to the Privy Council of England and was made joint principal secretary (the position which later became "Secretary of State") with Sir Thomas Smith. Smith retired in 1576, leaving Walsingham in effective control of the privy seal, though he was not formally invested as Lord Privy Seal.Cooper, pp. 87–88 Walsingham acquired a Surrey county seat in Parliament from 1572 that he retained until his death, but he was not a major parliamentarian.Adams et al.; Wilson, p. 156 He was knighted on 1 December 1577,Adams et al.; Hutchinson, p. 243; Wilson, p. 127 and held the sinecure posts of Recorder of Colchester, custos rotulorum of Hampshire, and High Steward of Salisbury, Ipswich and Winchester.Adams et al.; Hutchinson, pp. 244, 348 He was appointed Chancellor of the Order of the Garter from 22 April 1578 until succeeded by Sir Amias Paulet in June 1587, when he became Chancellor of the Duchy of Lancaster in addition to principal secretary.Adams et al.; Hutchinson, pp. 243–244
