Trench, Power Le Poer (1770–1839), Church of Ireland archbishop of Tuam, was born 10 June 1770 in Sackville (O'Connell) St., Dublin, third son (and second to survive childhood) among ten sons and nine daughters of William Power Trench, 1st earl of Clancarty, and his wife, Anne, daughter of Charles Gardiner (qv) of Dublin (her brother was Luke Gardiner (qv), 1st Earl Mountjoy). Richard Trench (qv), later 2nd earl of Clancarty, was Power's elder brother; a sister was grandmother of Sir William Henry Gregory (qv). The family had many connections in the Irish church, army, and landed gentry; Richard Chenevix Trench (qv) was distantly related. Power Trench attended schools in England and Ireland, and entered TCD as a pensioner in July 1787. He graduated BA on 13 July 1791, and was ordained deacon the following November, and priest on 24 June 1792. He was curate in the union of Creagh, in Galway, and subsequently held the union of Rawdonstown in Meath in plurality. He resided at Creagh, where he also acted as agent for his father's and father-in-law's Galway estates, and (in the unsettled political climate of the 1790s) was a captain of yeomanry. His biographer, J. D. Sirr (qv), notes that he scoured the country night and day for rebels, though he adds that many were saved from the gallows by Trench's interventions. A family historian noted that Trench combined in a ‘remarkable manner the athlete, man of business, and devoted minister’ (Cooke-Trench, 36). One could add that Trench's aristocratic, even princely, attitudes and manner coloured all that he did; in the emergency of the 1821 famine, he found it natural that he should practically govern Connacht.
On 21 November 1802 he was consecrated bishop of Waterford. He built churches and glebe houses in the diocese, and obtained an act of parliament that effectively refounded the school established by his predecessor Nathaniel Foy (qv). He was translated to the see of Elphin in 1809, and by patent of 29 October 1819 was created archbishop of Tuam. Two small dioceses, Achonry and Killala, were included in his care from 1834. Trench on several occasions, even as late as 1820, rode at the head of detachments of dragoons against Whiteboy aggression, and to quell a Ribbon affray, and is said to have outridden the professional soldiers.
Up to 1816 Trench was much more of an eighteenth-century prelate than a nineteenth-century one. He opposed the growing evangelicalism of his clergy, and in a visitation sermon of that year rebuked what he called unscriptural innovations. The piety and resignation shown by his young sister Lady Emily La Touche, on her deathbed in March 1816, greatly affected him, however, and as his views on faith and salvation changed, his objections to the doctrines of the evangelicals were finally overcome in an exchange of letters with his archdeacon, William Digby. Trench appears to have tried always to do everything superlatively well, and he now became a superlatively committed evangelical. For the rest of his life he was the enormously influential leader of an important revival, particularly in the western dioceses of the Church of Ireland. His appearance on the platform of the Hibernian Society meeting of 1819, to show his support, was ‘electrifying’ (Sirr, 85). The archbishop appointed young clergymen who were burning with missionary zeal to invigorate protestants and convert catholics, and he supported the Achill mission of Edward Nangle (qv). A by-product of what they hoped would be a second reformation in Ireland was a revival of enthusiasm for preaching in the Irish language, in hopes of communicating better with the local population. Trench at first declared that after 1832 he would only ordain men who could speak Irish; when that proved impracticable, he proposed unsuccessfully that a college should be set up in Tuam where the clergy could learn oral skills in Irish. Unused to failure, Trench then threw his weight behind a campaign to gather funds to set up a chair of Irish in the divinity school in TCD. In 1835 he made a submission to the board of the college, and eventually in 1840, just after the archbishop's death, his protégé Thomas Coneys (qv) was appointed as the first professor of Irish.
In 1820 Trench took a prominent and possibly decisive role in the trial of Queen Caroline in the house of lords; as a result of his courageous speech opposing her divorce, which offended the king, the archbishop may have forfeited the possibility of further advancement in the church. However, he found adequate scope for his great energy in reforming the archdiocese of Tuam. Trench was a notably exacting bishop, who demanded improvements in the keeping of records, in the catechising of children, and in pastoral care. Despite the poverty and small protestant populations of parishes in the west of Ireland, Trench, relying largely on donations from English dioceses, managed to increase the number of resident clergy and built new churches. He obtained large amounts of money to help feed the starving people in the periodic famines that characterised the early nineteenth century, and took great care to involve Roman catholic clergy in the work, in order to ensure that catholics as well as protestants were sustained. Particularly in the scarcity of 1821–2, Trench's work was of inestimable importance. Few could have equalled his record of activity and generosity; he rose every day at 4.00 a.m. and personally visited poor households to bring food, some of which was provided from his own resources. According to his fellow bishop John Jebb (qv), he was the ‘mainspring, the regulator, and the minute-hand of the whole charitable movement’ (quoted in Sirr, 160), and there was heartfelt gratitude among those whom he assisted.
As might be expected of someone with his beliefs, Trench was deeply interested in the education of the poor. He personally taught scores of ragged boys in a Sunday school in his palace in Tuam, and he initially supported the work of the London Hibernian Society, which was set up to provide schools for the poor. However, he became an implacable opponent of the Kildare Place Society, endowed with government funds after 1814, which attempted to provide non-denominational and non-contentious education, by limiting the role of religious instruction in its schools. Moves towards the establishment of what became the Irish national school system were still more vigorously attacked by the archbishop, who successfully mustered influential supporter in his campaign, and set out to ride roughshod over catholic and presbyterian opposition. He wrote to the duke of Wellington (qv) in 1829 that ‘no education is better than one not founded upon the sacred word of God’ (Sirr, 697). In his endeavour to ensure that catholic views on the scriptures in education were not to prevail, Trench in 1838 suggested the establishment of a Church Education Society, declaring that in supporting the Hibernian Society and Kildare Place Society, he and his fellow clergymen had been guilty of compromising their sacred principles. He called a meeting to plan the further campaign, at Tuam on 13 March 1839, but was unable to attend, and died 26 March 1839, apparently of typhoid fever, in his palace at Tuam. He was buried with his ancestors in the Trench family vault at Creagh, with a memorial in his cathedral; he was the last archbishop of Tuam, as following reforms in the church structures, his successors were to be enthroned as bishops.
He married (29 January 1795) his first cousin, Anne, only daughter of Walter Taylor of Castle Taylor, Co. Galway; they had two sons and six daughters. Two of his children in their turn married first cousins.