Cooper, Austin (1759–1830), antiquary, was born 15 February 1759 at Killinure, Co. Tipperary, third son among fourteen children of William Cooper, registrar of the diocese of Cashel, and his wife Jane (née Wayland). Cooper was educated in Cashel, and in 1774 entered the treasury office at Dublin Castle under the care of his uncle John Cooper, a clerk there; his younger cousin, Joseph Cooper Walker (qv), who also later become an antiquary, entered the office around the same time, and Gabriel Beranger (qv), the well-known antiquarian artist, was later appointed assistant ledger keeper in the Office. This unusual cluster of antiquarians in the treasury office must have been connected with the appointment of William Burton Conyngham (qv), generous patron of antiquarian studies, to the position of teller of the exchequer soon after Cooper became a clerk. It is reasonable to assume that Conyngham, who employed Beranger and others to visit and record Irish antiquities, encouraged young Austin to do the same. Cooper's subsequent promotion to paymaster to the pensioners on the civil and military establishments (which meant that he had to travel throughout Ireland) gave him the opportunity to describe, measure, and draw numerous ruins, mostly castles and churches. In 1793 Cooper was promoted to his retired uncle's position as chief clerk to the deputy vice-treasurer. From 1799 until his own retirement around 1806, he served as military clerk to the commissioners of the exchequer. In 1796 he was appointed deputy constable of Dublin castle, a post that he held until his death. He was also agent for several large estates throughout the country, and for the Erasmus Smith schools, and was a lottery ticket agent. His income from all his posts was considerable, and he is said to have won £20,000 (an immense sum at that time) on a lottery ticket. He was able to buy a good deal of property, including an estate at Kinsealy, Co. Dublin, and an impressive house at Abbeville, which was bought subsequently by James William Cusack (qv) and in the twentieth century was for many years the home of the taoiseach Charles Haughey (d. 2006).
Cooper was a member of the Dublin (later the Royal Dublin) Society and, according to family papers, a fellow of the Society of Antiquaries. His library, of over a thousand historical works and documents, included the impressive and valuable collection of the late W. B. Conyngham, which Cooper had bought. Conyngham's lost will was found in one of the books, too late to affect the disposition of his estate. Cooper's own work remained in manuscript form until 1942, when Liam Price (qv) edited and published selections from his surviving sketches, notes, and diaries. These cover parts of Leinster and Munster and show their author to have been a very perceptive fieldworker. His work is characterised by commonsense interpretation, rather than the rampant antiquarian speculation current among his contemporaries. Cooper's work was also edited by Peter Harbison, MRIA, and published as Cooper's Ireland (2001).
Austin Cooper married (12 July 1786), at St Annes church, Dublin, Sarah Mauvillian (Mauvillieu, McWilliam?), daughter of Timothy Turner, a lottery ticket agent. They had four sons and three daughters. Sarah Cooper died on 17 June 1830; Cooper himself died at his town house in Merrion Square on 30 August 1830, from the after-effects of fracturing his leg the previous year when his carriage overturned on the road between Dublin and Abbeville. A great-nephew, also Austin Cooper, was murdered in an agrarian outrage in Tipperary in 1838.