Alen, Sir John (d. 1561), lawyer and administrator, was the son of Warin Alen of Cotteshall, Norfolk, England, and cousin of his namesake John Alen (qv), archbishop of Dublin (1529–34) and a protégé of Cardinal Wolsey. He entered Gray's Inn in 1522, and from 1529 served in Dublin as secretary to his cousin and later as clerk of the council. Alen became one of Thomas Cromwell's chief agents in reforming Irish administration, and was the first master of the rolls (previously only a clerkship) and a member of the council (July 1533); these appointments followed a visit to London. He was again in London at the time of the Silken Thomas rebellion in 1534. The following year he was appointed chancellor of the exchequer and in 1536 became clerk of the Irish parliament. In 1538 he was first appointed keeper of the great seal (31 July), then chancellor (18 October). In 1539 he headed the commission for suppressing religious houses.
Alen was allied with the Butler interest in Irish politics; his chief rival and successor as chancellor, Sir Thomas Cusack (qv), was allied with the Kildare interest; both, however, agreed on the main lines of reform and the extension of conciliar administration. Alen's role in the movement for reform was apparent in autumn 1533 when he submitted to Cromwell the views of a prominent group of reformers, both churchmen and members of the Irish council, which influenced Cromwell's ‘ordinances for the government of Ireland’. Throughout the 1530s Alen consistently argued that an expanded English colony should be the primary aim of government policy. As for the rest of Ireland, including Gaelic and Gaelicised Ireland, Alen saw the task of policy makers as devising a system of government for ‘this land being in several monarchies’ (quoted in Bradshaw, 128); the basis for dealing with this should be the practice of peace indentures. In 1538 he returned from a visit to court with permission to open negotiations with a number of Gaelic lords about granting them status and title under the crown, though nothing came of this until the deputyship of Sir Anthony St Leger (qv).
After making accusations against St Leger, Alen was recalled to England on charges of corruption in 1546, deprived of office, and committed to the Fleet prison. In Edward VI's reign he was restored as chancellor (22 April 1548) and knighted, but quarrelled again with St Leger, and was dismissed when the latter became deputy for the fourth time in 1550. Reinstated on the council in 1554, he was not active after 1556, and resided in England under Mary I; he became, however, MP for Kinsale in 1560 and died c.1561. He had been granted the priory of St Wolstan's, Co. Kildare, in 1536, the foundation of his family's estates in Ireland. He was buried in Donocomper church, near St Wolstan's, and was succeeded by his nephew, John Alen.