James Margetson (1600 – 26 August 1678) was an English churchman, Church of Ireland Archbishop of Armagh from 1663 till 1678.
He was educated at Peterhouse, Cambridge,[1] and returned after ordination to Yorkshire, where he attracted the notice of Thomas Wentworth, then Lord President of the North, who took him as chaplain to Ireland in 1633.
It appears from the correspondence of William Laud and Strafford (as Wentworth now was) intended to restore the almost ruinous cathedral of Christ Church, but that he found neither time nor money.
When the Irish Rebellion of 1641 broke out, Margetson was distressed from the failure of income; by 1647 Dublin was in the hands of the English parliament, and the Anglican clergy were invited to use the Directory of Public Worship instead of the Book of Common Prayer; one bishop and seventeen clergymen, of whom Margetson was one, refused to hold their churches on these terms.
Margetson's eldest son, John, was killed at the siege of Limerick, being then a major in William III of England's army, leaving a daughter, Sarah, from whom the earls of Bessborough and Mountcashel are descended.