A historian, a scholar and a key figure in the religious debates of the 16th century, Ussher was born in Dublin (either on Nicholas St or 57 High St across from the old Christchurch Synod Hall) on the 4th January 1581 and baptised in the Church of Ireland St Nicholas Within. He was born into a prosperous merchant family, but one that was torn by the religious divisions of the time. Most of the Usshers conformed to the Church of Ireland, notably Henry Ussher, Church of Ireland archbishop of Armagh from 1595 to 1613, who played an important role in the creation of Trinity College, Dublin in 1592. His mother remained Catholic; her brother was the famous historian Richard Stanyhurst (1547-1618), in later life a Jesuit priest .
James Ussher was one of the first to attend Trinity College Dublin, gaining his BA c. 1597 and MA in 1601. He was ordained by his uncle Henry Ussher in December 1601 and in 1602 took his first trip of many to England, in search of books for Trinity College Library. During his trips to London he made many antiquarian connections with figures such as Henry Savile and John Seldon. He graduated in Divinity in 1607, immediately becoming Professor of Theological Controversies. In 1613 he married Phoebe Challoner, daughter of the vice-provost of Trinity Luke Challoner, and published his first work, Gravissimae Quaestionis, de Christianarum ecclesiarum, in occidentis praesertim partibus, ab apostolicis temporibus, ad nostram usque aetatem, continua successione & statu, historica explicatio (London, 1613). This work gave an account of medieval heretical groups drawing on original sources; however it also had the polemical purpose of tracing the rise of the Anti-Christ in Roman Catholic church, and the identification of groups such as the Cathars as proto-protestants.
Ussher graduated DD in 1614 and became vice-chancellor of Trinity in 1615. He is also credited with playing a large part in the creation of the Church of Ireland’s first full Confession of Faith. These articles were an advance on the 39 Articles on which they were based, they allowed more accommodation of puritan ideas than the equivalent in the Church of England (for example, allowing more leeway on the question of bishops) and did not require subscription. Ussher became Bishop of Meath and Clonmacnoise in 1621 and finally was appointed Archbishop of Armagh by James I of England in 1625. It should be noted that of the twenty-five bishops James I placed in the Church of Ireland in his lifetime, Ussher was the only one born in Ireland and educated at Trinity 
Ussher not only was involved in the creation of articles for the Church of Ireland but effectively gave the Church its creation myth. Growing out of Irish controversies about the status of St. Patrick, Ussher argued (and believed himself) that the Church of Ireland was a return to the original early Christian Irish church, not a departure from it. (For more see McCafferty (1997) and the post Appropriating Patrick.) An extension of Gravissimae Quaestionis, it is still valuable today since many of the original manuscripts Ussher used, particularly the Irish ones, are no longer extant.
However Ussher’s Church of Ireland did not survive long, if it ever existed. In 1634 the Church of Ireland was forced to adopt the Thirty-Nine Articles and the Irish Articles were suppressed. Though he remained nominally the Primate of Ireland, control of the church passed to Laud, Archbishop of Canterbury (who was so involved that he incensed Richard Boyle, Earl of Cork by moving Boyle’s family monument in St Patricks), Wentworth the Lord Deputy and Bramhall, Bishop of Derry.
Perhaps this was inevitable. Gilbert Burnet (historian and friend of Robert Boyle) argued that Ussher “was not made for the governing part of his function. He had too gentle a soul to manage that rough work of reforming abuses”. In the 1630s he chose (or it was chosen for him) that his focus would be scholarship. As well as his works on the early church and his famous or infamous chronology (1650/54/58), Ussher wrote on the question of predestination via a work (1626) on the ninth-century theologian Gottschalk and (1644) demonstrated that several letters attributed to Ignatius of Antioch were not written by him (one of the few scholarly conclusions of Ussher’s that still stands). All these show Ussher’s careful scholarship and his tendency to appeal to the past to answer current controversy.
Ussher was in England when rebellion in Ireland broke out in 1641 and never returned to Ireland. In the first year of the Long Parliament, Ussher refused to be involved in the theological debates of the Westminster Assembly, but he did get involved in public campaigns to support the institution of bishops in the established church (episcopacy). He also wrote the posthumously printed Reduction of Episcopacy Unto the Form of Synodical Government (1656), which attempts to forge a compromise government of the church consisting of interlocking synods from parish to province to state, with bishops (possibly renamed superintendents) playing an unspecified role. There is evidence that Ussher later repudiated this scheme in favour of defending full-blooded episcopacy.
Yet, as can be seen from the Church of Ireland articles of 1631, Ussher sought to establish co-existence of protestant Christians rather than to provoke ongoing controversy. He, along with bishops William Bedell (Kilmore) and John Richardson (Ardagh) sent a positive letter in 1734 to John Dury who had written to them about his ecumenical project  (one in which others, such as Lady Ranelagh, took an interest). Ussher continued to correspond with Dury until Dury’s involvement with the Westminster Assembly . This was only part of the wide correspondence that Ussher was involved in, spanning the Boates, whose book he had published, the Hartlib circle and, despite Ussher’s opposition to toleration of Catholicism, priests and friars. These included his Catholic relations and, indirectly and cautiously on their side, with scholars such David Rothe and Luke Wadding through the Jesuit William Malone and the Franciscan Thomas Strange. In 1641, Fr Brendan Conor wrote to Ussher in London (my additions in angle brackets) 
I was expecting letters from Belgium, from the distinguished Puteanus and our Stanihurst <William, Jesuit and cousin of Ussher>, which have not yet arrived, [but which] will swiftly be brought to satisfy your wishes. At the same time you will see the most welcome [letter] of Colgan, my colleague in [these] studies, and together with those, the letters of Columbanus which you seek. […] The iniquity of time separates us, but your sincere [friend] Brendan will not cease to pray that God’s kindness may join us [again].
[…]I beg three things of you, no less vehemently than confidently: that you may fee [back] home from the Pharaonites <the parliamentarians>; that you should spend time, which is now precious, on the better kind of studies to the furthest limit; and that you may bring back a bundle of manuscript codices like spoils from Egypt.
Unable or unwilling to follow this advice, Ussher remained in England until he died suddenly on 21st March 1656 in Reigate. His last words were, “O Lord forgive me, especially my sins of omission.” His friends intended to bury him privately in Reigate but Cromwell intervened, and Ussher was buried in St. Erasmus’ Chapel, Westminster Abbey on 17 April, 1656 .
Alan Ford (2004) ‘Ussher, James (1581–1656)’, Oxford Dictionary of National Biography, Oxford University Press; online edn, Oct 2009 [http://www.oxforddnb.com/view/article/28034]
James Carr (1895) The Life and Times of James Ussher, London: W. Gardner, Darton and co [archive.org]
Elizabethanne Boran (2014) The Edward Worth Library: Republic of Letters: The Ussher Project [http://edwardworthlibrary.ie/the-republic-of-letters/the-ussher-project/ accessed 4 Jan 2016] – the project
Archiseek (2010) 1707 St Nicholas Within [accessed 4 Jan 2016]
John McCafferty (2004) “Ussher, James (1581-1656)” in Thomas Duddy (ed) Dictionary of Irish Philosophers, Bristol: Thoemmes Continuum, pp. 353-356.
John McCafferty (1997) “St Patrick for the Church of Ireland: James Ussher’s Discourse” in Bullán, Vol 3, No 2. [academia.edu]
Reformation Anglicanism (2014) 4 Jan 1581: Birth of Mr. (Abp.) James Ussher (includes an account of Ussher’s funeral and a picture of the stone placed over his grave by George Salmon, Provost of Trinity in 1904.)
 Alan Ford (2004) ‘Ussher, James (1581–1656)’, Oxford Dictionary of National Biography, Oxford University Press; online edn, Oct 2009 [http://www.oxforddnb.com/view/article/28034, accessed 4 Jan 2016]
 James Carr (1895) The Life and Times of James Ussher, London: W. Gardner, Darton and co, pp. 8-9.
 Ford (2004); Elizabethanne Boran (2015) “Life of James Ussher” on The Edward Worth Library: Republic of Letters [http://edwardworthlibrary.ie/The-Republic-of-Letters/The-Ussher-Project/Life-of-James-Ussher/ accessed 4 Jane 2016]
 John McCafferty (2004) “Ussher, James (1581-1656)” in Thomas Duddy (ed) Dictionary of Irish Philosophers, Bristol: Thoemmes Continuum, pp. 353-356.
 Ford (2004).
 McCafferty, 2004, p. 354.
 McCafferty (1997), p. 97.
 Gilbert Burnet (1685) The life of William Bedell, p. 86, quoted in Ford, 2004.
 McCafferty (2004), p. 354.
 McCafferty (2004), p. 355.
 Elizabeth Doran (ed) (2015) The Correspondence of James Ussher 1600-1656, Volume II, pp. 630-632.
 Doran (2015), Vol III, p. 1095.
 Doran (2015), Vol III, pp. 859-861. For the complex dividing lines between public and private correspondance for Ussher and his contemporaries, see Doran (2015), Vol I, pp. xlvii-xlviii.
 Ford (2004).