Wilson is born in County Longford and a long-time opponent of the Irish Home Rule movement. He joins the British army in 1884 and sees action during the Boer War. He is assigned to British army headquarters during the infamous Curragh incident and supports the near-mutiny of British officers who refuse to lead troops against Ulster opponents of home rule. He serves in France during the World War I and, when the war ends, continues his staunch support of the Unionist cause while serving as Chief of General Staff. He is a strong supporter of the coercion tactics of the British in Ireland during the Irish War of Independence, even suggesting that the leaders of Sinn Féin be executed. He leaves the army when David Lloyd George decides not to renew his term as chief of staff and is elected Member of Parliament (MP) for North Down as a Conservative in 1922. In Parliament, he urges even stronger coercion methods than those then being carried out by the Black and Tans.
On June 22, 1922, two London-based volunteers of the Irish Republican Army, Reginald Dunne and Joseph O’Sullivan, assassinate Wilson outside his house at 36 Eaton Place at approximately 2:20 PM. He is in full uniform as he is returning from unveiling the Great Eastern Railway War Memorial at Liverpool Street station at 1:00 PM. He has six wounds, two of them fatal wounds to the chest.
Stories later circulate that the first shot misses but rather than taking shelter in the house, he draws his sword and advances on his attackers, who are able to shoot and kill him. These stories often stress that he dies a martyr. His housemaid testifies that she found his drawn sword lying by his side. These details do not feature in the witness accounts by Reginald Dunne, which is smuggled out of prison, the inquest testimony of one of two road menders working nearby, and the taxi driver who had just dropped Wilson off. One of the road mender’s accounts, as published in the Daily Mail, mentions Wilson turning on his attackers with the words “you cowardly swine!” but this is believed to be a possible embellishment by the newspaper.
Two police officers and a chauffeur are also shot as the men attempt to avoid capture. They are then surrounded by a crowd and arrested by other policemen after a struggle. Dunne and O’Sullivan are convicted of murder and hanged on August 10, 1922. On the day Wilson’s killers were hanged, Currygrane, the family homesite in Ballinalee, County Longford is burned to the ground, possibly as a reprisal although possibly as an unrelated part of the unrest in that county.
Wilson’s widow blames the government for his death and is only persuaded to allow government representation at the funeral on the grounds that not to do so would be disrespectful to the King. Wilson’s funeral is a public affair attended by David Lloyd George and the cabinet, Ferdinand Foch, Robert Nivelle and Maxime Weygand from France as well as many of his former army colleagues including John French, Nevil Macready, Douglas Haig and William Robertson. He is buried in the crypt of St. Paul’s Cathedral in London.