King, Sir John (d. 1637), administrator and landowner, was a member of a Yorkshire family; no further details of his background are known. He appears to have begun his career in Ireland in the employ of Sir Richard Bingham (qv), lord president of Connacht, acting as Bingham's secretary in July 1585, and continuing in his service until September 1596 at least. By September 1600 he was deputy to the vice-treasurer, Sir George Carey, a position he held until at least March 1606. On 12 July 1603 he was appointed clerk of the crown in the Irish chancery, and the following month he was also appointed clerk of the hanaper. He surrendered his patents on 26 January 1607, and three days later received a regrant of these offices, jointly with Francis Edgeworth. In October 1627 the two posts were united and regranted to King and his son John, who was married to Edgeworth's daughter Margaret. On 1 August 1609 he was made muster master general and clerk of the cheque of the army in Ireland, replacing Sir James Fullerton.
King's increasing importance in the administration led him to be admitted to the Irish privy council (June 1609) and to the council of Munster (20 May 1615), and to his knighthood (7 July 1610). He also served on numerous significant commissions. In August 1614 he was one of six senior officials named to assist the lord deputy, Sir Arthur Chichester (qv), in the plantation of Co. Wexford, and in 1616 and 1622 was commissioned to investigate how the plantation of Ulster had been implemented. He was a commissioner of the court of wards in Ireland (1610–22), and in June 1615 was named to a commission for a general visitation throughout the kingdom of Ireland. In June 1627 he was one of those charged with reporting to the king on a dispute between Richard Boyle (qv), 1st earl of Cork, and Henry Wright and Richard Blacknall over debts Blacknall had accrued while leasing Boyle's ironworks at Kilmacke (Kilnamack), Co. Waterford.
King also continued his association with Connacht. He was constable of Boyle abbey, where he commanded a small garrison of ten to fifteen soldiers, and served as MP for Co. Roscommon in the Irish house of commons in 1613. At the opening session of the parliament he witnessed the violent clashes between catholic and protestant members, the trouble sparked by the efforts of the administration to ensure a protestant majority in the house. King's own election was questioned, owing to the actions of Sir Oliver St John (qv), vice-president of Connacht, but the result was allowed to stand and King contributed to the protestant majority. He also served on commissions dealing with the composition of Connacht (1611, 1616), and in 1615 he was one of the commissioners charged with the governance of the province during the absence of the president, Richard Burke (qv), 4th earl of Clanricard (d. 1635).
King amassed extensive landholdings scattered throughout Ireland. By 1604, in addition to the site of the former Cistercian abbey at Boyle, where he was constable, he held leases, together with John Bingley (qv), for the Augustinian abbey at Cong, Co. Mayo, the Augustinian abbey of the Holy Trinity at Ballintober, Co. Mayo, and the Fratres Cruciferi priory of St John at Athy, Co. Kildare. By 1607 he had added the Augustinian abbey at Kells, Co. Antrim, and the Augustinian abbey at Muckamore, Co. Antrim, as well as numerous other properties. In 1615 he was living at Baggotrath, near Dublin. He died 4 January 1637 at Lichfield, Staffordshire, and, in spite of directions in his will (dated 31 May 1636) that he be buried either there or at St Michan's church, Dublin, he was laid to rest at Boyle on 30 March 1637.
King married (date unknown) Catherine (d. 14 December 1617), daughter of Robert Drury; they had six sons – Sir Robert King (qv) (d. 1657), who was appointed clerk of the cheque in 1638 and whose son John King (qv) was made Baron Kingston in 1660, John, Roger, Edward, Henry, and Adam – and three daughters, Mary, Margaret, and Dorothy.