Bagenal’s father, one of the largest landowners in county Carlow, secured his election for the county in 1768 by duelling with one opponent and scaring off another, and preferred ‘amusements’ to ‘business’. In consequence the bulk of the estate was sold about 1784, and although Walter Bagenal later entered into possession of Dunleckney, he took up residence in England.
Although it was remarked of him in May 1804 that he would vote with his colleague Latouche, like whom he supported Calcraft’s motion on the Prince of Wales’s debts, 4 Mar. 1803, Bagenal (equally silent in debate) was rather more inclined to opposition. On 19 Mar. and 25 Apr. 1804 he was in the lobby against Addington’s tottering ministry and, unlike Latouche, he was a decided opponent of Pitt’s second ministry who also voted for the Catholic petition, 14 May 1805. The Grenville ministry could count on his support, and although he left the House without voting on the issue of their dismissal in April 1807,
Unlike most Irish Members, Bagenal seldom went to Ireland; a visit in 1805 was announced in The Times.
