Denis McCullough (24 January 1883 – 11 September 1968) was a prominent Irish nationalist political activist in the early 20th century, who served as President of the Irish Republican Brotherhood (IRB) from 1915 to 1916.
Early career – IRB activist
McCullough was born at 1 Barrack Street, Belfast, on 24 January 1883, to Daniel McCullough, a publican, and Margaret Magee.
McCullough was a separatist nationalist from an early age. Both his father and grandfather were in the Irish Republican Brotherhood (IRB), as was his brother. When he was 17, his father had him inducted into the IRB at the side door of a pub by a man who seemed to view the ritual as an unpleasant distraction to a night of drinking. The event disillusioned McCullough with the IRB, and he took it upon himself to revitalise the organisation, with assistance from, among others, Bulmer Hobson and Seán Mac Diarmada. The trio founded the Dungannon Clubs as a non-sectarian, republican, separatist organisation (it was later absorbed into Sinn Féin), for recruitment. They worked to remove "armchair republicans" from positions of power. Their cause prospered with the return of veteran Fenian Tom Clarke to Ireland in 1907.
President of IRB and Easter Rising
McCullough was elected to fill the vacant seat of the President of the IRB late in 1915, a position he held during the 1916 Easter Rising, though he took no active role in the rising itself. He was not a member of the Military Committee that was responsible for its planning. It is likely that the other members of the three-man IRB executive, Clarke and MacDermott (the treasurer and secretary) supported his nomination as president because, as he was isolated in Belfast, he would be in no position to interfere with their plans. Nevertheless, during Holy Week he got word of what was afoot and travelled to Dublin to question Clarke and MacDermott, who avoided him as long as they could. Eventually, they informed him of their plans, which he came to support. Although McCullough was an officer of the Irish Volunteers, in charge of 200 men in Belfast, it was decided that Belfast would not take part in the rising, given that the dominance of the Ulster Volunteers in the northeast could lead to sectarian civil war.
McCullough stated in his application for an Irish military pension in 1937 that, "I brought out my men in Belfast and mobilised them at Coalisland to cooperate with the Tyrone Volunteers in accordance with orders from Pearse and Connolly received by me. Their orders were to bring all available men and arms across Ulster to Connaught to join Mellows there. They were insistent, especially James Connolly, that we were to 'fire no shot in Ulster'. I thought these orders were mad ones but determined to carry out [the] orders if possible."
McCullough led Volunteers in his area to Dungannon, County Tyrone, from where they would link up with Liam Mellows in Connacht.
On his release, he married Agnes Ryan, a sister of politician James Ryan and of Josephine Ryan and Phyllis Ryan,
It has been argued that as president of the Irish Republican Brotherhood at the time of the Easter Rising, the title President of the Irish Republic was by rights his, and not Patrick Pearse's. However, as he had no real role in the planning of the insurrection and was not in the vicinity of Dublin, where it was clear the leadership would need to be, it is understandable that Pearse was given the title instead. McCullough's decision not to fight in the Easter Rising cost him his pre-eminent position among Belfast republicans. One, Sean Cusack, later said that he told McCullough, "we all felt he had, to some extent, let us down".
War of Independence and Treaty
McCullough felt he was sidelined during the Rising and left the IRB. He was an ordinary volunteer in the Irish War of Independence (1919–1921), during which he was arrested and imprisoned by the British several times and held for long periods. He was reportedly unaware that Michael Collins was continuing to covertly arm the IRA in Ulster until August 1922, partly to protect nationalists there and partly to try to bring down the Northern Irish state. After the Treaty, he was sent by George Gavan Duffy to the United States to make contact with Irish republican organisations there. He did not contest the subsequent general election, held in June 1927.