Denis O'Brien was a veteran of what conflict that led to the establishment of the Irish Free State?
Denis O'Brien (police officer) Detective Sergeant Denis O'Brien, Registration Number: 8288 (17 June 1899 – 9 September 1942), often called "Dinny O’Brien", was a veteran of the Irish War of Independence and the Irish Civil War. He joined the Garda Síochána in 1933 and was killed by the Anti-Treaty IRA.
Battle of New Ross (1798) On 4 June 1798, the rebels advanced from their camp on Carrigbyrne Hill to Corbet Hill, just outside New Ross town. The battle, the bloodiest of the 1798 rebellion, began at dawn on 5 June 1798 when the Crown garrison was attacked by a force of almost 10,000 rebels, massed in three columns outside the town. The attack had been expected since the fall of Wexford town to the rebels on 30 May and the British garrison of 2,000 had prepared defences both outside and inside the town. Trenches were dug and manned by skirmishers on the approaches to the town while cannon were stationed facing all the rapidly falling approaches and narrow streets of the town to counter the expected mass charges by the rebels, who were mainly armed with pikes.