William John Twaddell, a Unionist politician from Belfast, Northern Ireland, is assassinated by the Irish Republican Army (IRA) in Belfast city centre on May 22, 1922.

Twaddell is born in Belfast in 1884. He is a draper who is educated at a Belfast primary school.

Twaddell is a member of the Ulster Unionist Party (UUP) and from 1910 he is a member of Belfast City Council. In November 1921, he and Robert Boyd organise the Ulster Imperial Guards as a paramilitary force of 21,000 men. He is elected to the Parliament of Northern Ireland for Belfast West in the 1921 Northern Ireland general election and sits until he is assassinated on May 22, 1922, by the Irish Republican Army. He is walking in Garfield Street off Royal Avenue, to his business, a short distance away, followed closely by his assassins.

Twaddell’s death precipitates a clamp-down on the IRA in Northern Ireland and 350 IRA members are interned. Seamus Woods, who is interned on HMS Argenta during the clampdown, is charged with his murder. Woods, who had joined the Irish National Army, is trying to control irregular elements within the IRA. By agreement with the government of Northern Ireland, two officers of the Irish National Army are given permission to travel to the trial. General J. J. “Ginger” O’Connell and Commandant Charles McAlister give evidence and Woods is found not guilty. A total of 724 people are interned in Northern Ireland up to the end of 1924.

Twaddell was buried at Drumcree Church cemetery, Portadown, County Armagh, Northern Ireland, where his headstone says that he was “foully murdered in Belfast.”