Ussher reached London early in December 1623, and remained in England till the beginning of 1626. He preached before James at Wanstead on 20 June 1624; in the same year he was admitted a member of Gray's Inn; at its close he published his ‘Answer’ to William Malone [q. v.] On 22 March 1624–5 he was appointed by patent archbishop of Armagh, in succession to Hampton. He was then living at Much Hadham, Hertfordshire, where his friend George Montaigne [q. v.], bishop of London, had a country house, now known as the Palace. In January 1624–5 he had preached a funeral sermon for Theophilus Aylmer, the late rector. Aylmer's successor, Peter Hausted [q. v.], is a link between Ussher and Jeremy Taylor [q. v.], being in charge of Uppingham on Taylor's appointment. Weekday preaching in Essex threw Ussher into a quartan ague; he lay ill at Hadham several months. In November, still ailing, he became the guest at Drayton Lodge, Northamptonshire, of John Mordaunt (afterwards first Earl of Peterborough) [see under Mordaunt, Henry, second Earl]. Mordaunt had become a Roman catholic, his wife Elizabeth, granddaughter of Charles Howard, earl of Nottingham [q. v.], remaining protestant; on her motion Ussher was to dispute the points in controversy with Oswald Tesimond [q. v.], known as Philip Beaumont. After three days' discussion, Tesimond retired; Mordaunt returned to the Anglican church. By 22 March 1626 Ussher was at Drogheda, under treatment by Thomas Arthur, M.D. [q. v.], who took him to the island of Lambay, which he left for Dublin ‘evicto morbo,’ on 8 June. He must have journeyed to Oxford soon after 14 June, if Wood is right in saying that he lodged in Jesus College at the time of his incorporation as D.D. (24 July). Parr says he returned to Ireland in August, but this is inconsistent with the statement that he was in England at the time of his mother's death.
Ussher's name heads the list of twelve Irish prelates, who met in Dublin and signed (26 Nov. 1626) a protestation against toleration of popery [see Downham or Downame, George]. Some relief had been proposed for Roman catholics in return for their army contributions. Against this Ussher preached as a corrupt bargain; and in an elaborate speech (30 April 1627) he urged that it was to the interest of Roman catholics to support the army without relief. In the previous month he had expressed to Robert Blair (1593–1666) [q. v.] his desire for the removal of grievances felt by the nonconforming puritans. As vice-chancellor he took now a large share in the affairs of Trinity College. The appointment of William Bedell [q. v.] as provost (16 Aug. 1627) was mainly his work, on the failure of overtures to Richard Sibbes [q. v.] Their relations became strained soon after Bedell's elevation (1629) to the sees of Kilmore and Ardagh. Ussher disapproved of Bedell's leniency to Roman catholics, and was averse from the policy of encouraging the Irish language as a means of religious instruction.
Ussher's correspondence with Laud began in 1628, and was maintained till 1640, with no lack of cordiality on either side. In love of learning, in reverence for antiquity, and in opposition to Rome, they had common ground, notwithstanding their adhesion to different theological schools; and though Ussher had none of Laud's passion for uniformity, he fully recognised the duty of allegiance to constituted authority. In September 1631 he interceded with Robert Echlin [q. v.], his suffragan, for leniency towards the Scottish nonconformists in Down; but in the following May, the crown having issued instructions, he declined to interfere. He carried out the king's order in regard to the sermon by George Downham against Arminianism (Elrington's suspicion of the authenticity of the letter, 8 Nov. 1631, is unfounded), though he had himself just published an extreme view of predestination in his ‘Gotteschalci Historia.’ On Laud becoming archbishop of Canterbury (1633), Ussher took immediate steps to procure his election (May 1634) as chancellor of Trinity College.
It has been assumed that Strafford, in conjunction with Laud, took measures to lessen Ussher's influence. Urwick urges in support of this view the appointment of William Chappell [q. v.] as provost of Trinity, but the facts will not bear this construction. On 26 June 1634 the long-pending dispute between the sees of Armagh and Dublin, for the primacy of all Ireland, was decided by Strafford in favour of Armagh (Ussher's paper on the controversy is printed in Elrington's Life, App. vi.). Ussher preached at the opening of the Irish parliament on 14 July. In the Irish convocation, which met simultaneously, the main question was that of the adoption of the Anglican articles and canons. Ussher had a plan for substituting the Anglican articles for the Irish ‘without noise, as it were aliud agens.’ Difficulties arose, and Strafford insisted on the adoption of the Anglican articles without discussion, which was done (November 1634), with one dissentient voice, in the lower house.
