Agar, James (1713–69), of Ringwood, Co. Kilkenny, MP and landowner, was born 7 September 1713, younger son of James Agar (1672–1733) of Gowran, Co. Kilkenny, MP, and his second wife, Mary (née Wemys). He was educated at the Rev. Edmund Lewis's school, Kilkenny, before graduating BA (1733) and LLD (1748) from TCD. In 1736 Agar, a burgess on the corporation of the borough of Gowran, initiated court proceedings against his brother Henry Agar (1707–46), MP for the borough, accusing him of exceeding his authority by attempting to act as portreeve on the corporation for two consecutive years. Agar lost the case but was elected MP for Gowran (1747–60) on his brother's death. He showed some independence but normally supported the government, voting for the money bill in 1753, and was a member of twenty-one committees in the house of commons (1753×60). As MP for Tulsk, Co. Roscommon (1768–9), he was described in a government report, ‘An alphabetical list of the house of commons with observations, May 19 1769’, as an independent member – attached neither to the government nor to the undertakers – who had purchased his seat, a gentleman of large fortune who would readily ask favours and if wooed by the government, would probably support it.
The patronage of Callan, a parliamentary borough in Co. Kilkenny, had long been disputed between the Agar and Flood families; the agreement in the 1710s to share the representation of the borough had broken down and the Flood family had become dominant. During the late 1750s Agar determined to wrest control of the Callan corporation from the Flood faction. From 1758 the annual elections to the key position of sovereign of the corporation were bitterly contested and marked by such violent exchanges that Callan acquired a reputation for ‘tumult and disorder’ (Kelly, Henry Flood, 51). Control was retained by the Flood family, which provoked Agar into much litigation, challenging the basis of their command of the borough. Elected MP for Callan (1761), Agar was unseated on petition by Henry Flood (qv), who was returned in Agar's place, thus increasing the enmity between the families. Relationships deteriorated so that in 1763 Agar was bound over ‘to keep the peace towards all his ma[jes]ties subjects and in part[icu]lar Henry Flood Esqr for one whole year’ (Kelly, ‘That damn'd thing’, 100). In 1765 Agar bought the Callan estate from Lord Desart, thereby commanding most of the lands of the borough; he established a weaving industry, probably recruited French workers, and claimed the patronage of the corporation as his right as lord of the manor. Henry Flood, probably fearful of losing control of the borough, publicly assaulted Agar, who challenged him to a duel, which they fought in Holyhead in June 1765. Following further electoral contests and violent incidents, Agar again challenged Flood to a duel: with their seconds in attendance the protagonists met 25 August 1769 in Dunmore Park, near Kilkenny. Agar's first shot missed; he shouted ‘Fire, you scoundrel’ (ibid., 103), and Flood shot him dead. The Agar–Flood duel stimulated intense public interest due to the high profile of the antagonists and their well known rivalry; it helped to popularise the code of honour and contributed to an environment where duelling became respectable. The Agar family initiated court proceedings against Flood, who was tried for murder (1770), found guilty of manslaughter in his own defence, and freed.
Agar married (6 July 1741) Rebecca, daughter of William Flower, 1st Baron Castle Durrow, and his wife Edith (née Caulfeild); they had four sons and two daughters. Their third and eldest surviving son, George Agar (1754–1815), MP, was born 18 April 1754. He was educated in England at Eton College before matriculating (1770) for Trinity College, Cambridge, but left before graduating. He inherited the Callan estate and the family rivalry. Reaching an agreement with Henry Flood, he gained the two Callan parliamentary seats from the Floods on petition in 1777, retained them in the 1783 election, and became the undisputed patron of Callan corporation. In parliament, he wished to be considered as independent but generally voted against the government. Appointed privy councillor (1789), he was created Baron Callan (1790). At the act of union (1801), he was one of the twenty-eight original representative peers for Ireland and was awarded £15,000 compensation for the loss of his patronage from the borough of Callan. Unmarried, he died 9 October 1815 and his title became extinct. The youngest son, Charles Agar (1755–89), was elected MP for Kilkenny city (1778), but a successful petition was entered against him, accusing his supporters of bribery; and Gervase Parker Bushe (qv), who had acted as second to Flood in the duel with James Agar, was elected. Charles abandoned politics, entered the church, and became archdeacon of Emly (1782–8). He married a Miss Bambrick of Queen's Co. (Laois); there were no surviving children. James Agar's nephews included James Agar (qv) (1735–89), Viscount Clifden, and Charles Agar (qv), earl of Normanton and archbishop of Dublin.