The Clerkenwell explosion, also known as the Clerkenwell Outrage, is a bombing that takes place in London on December 13, 1867. The Irish Republican Brotherhood (IRB), nicknamed the “Fenians“, explode a bomb to try to free one of their members being held on remand at Clerkenwell Prison. The explosion damages nearby houses, kills 12 people and causes 120 injuries. None of the prisoners escape.

The whole of Ireland has been under British rule since the end of the Nine Years’ War in 1603. The Irish Republican Brotherhood is founded on March 17, 1858 with the aim of establishing an independent democratic republic in Ireland, and the Fenian Brotherhood, ostensibly the American wing of the Irish Republican Brotherhood, is founded in New York City in 1859.

On November 20, 1867, Ricard O’Sullivan Burke and his companion Joseph Casey are arrested in Woburn Square in London. Burke had purchased weapons for the Fenians in Birmingham. Burke is charged with treason and Casey with assaulting a constable. They are remanded in custody pending trial, and imprisoned at the Middlesex House of Detention, also known as Clerkenwell Prison.

Burke’s IRB colleagues try to free him on Thursday, December 12, without success. They try to blow a hole in the prison wall while the prisoners are exercising in the prison yard but their bomb fails to explode. They try again at about 3:45 PM the following day, December 13, using a barrel of gunpowder concealed on a costermonger‘s barrow. The explosion demolishes a 60-foot section of the wall, but no one escapes. The prison authorities had been forewarned and the prisoners were exercised earlier in the day, so they are locked in their cells when the bomb explodes. The blast also damages several nearby tenement houses on Corporation Lane on the opposite side of the road, killing 12 people and causing many injuries, with estimates ranging from around 30 to over 120.

Charges are laid against eight, but two turn Queen’s evidence. Michael Barrett and five others are tried at the Old Bailey in April 1868. Lord Chief Justice Sir Alexander Cockburn and Baron George Bramwell preside with a jury. The prosecution is led by the Attorney General Sir John Karslake and the Solicitor General Sir William Baliol Brett supported by Hardinge Giffard QC and two junior counsel. Defence barristers included Montagu Williams and Edward Clarke.

Barrett, a native of County Fermanagh, protests his innocence, and some witnesses testify that he was in Scotland on December 13, but another identifies him as being present at the scene. Two defendants are acquitted on the instructions of the presiding judges in the course of the trial, leaving four before the jury. Following deliberations, three of the defendants are acquitted, but Barrett is convicted of murder on April 27 and sentenced to death. Barrett is hanged by William Calcraft on the morning of Tuesday, May 26, 1868 outside Newgate Prison. He is the last man to be publicly hanged in England, with the practice being ended from May 29, 1868 by the Capital Punishment Amendment Act 1868.

The trial of Burke and Casey, and a third defendant, Henry Shaw, begains on April 28, all charged with treason. The prosecution claims that Burke had been involved in finding arms for the Fenians in Birmingham in late 1865 and early 1866, where he was using the name “Edward C Winslow.” The case against Casey is ultimately withdrawn, but Burke and Shaw are found guilty of treason on April 30 and sentenced to 15 years and 7 years of penal servitude respectively.

The bombing enrages the British public, souring relations between England and Ireland and causing a panic over the Fenian threat. The radical, Charles Bradlaugh, condemns the incident in his newspaper, the National Reformer, as an act “calculated to destroy all sympathy, and to evoke the opposition of all classes.” The Metropolitan Police form a Special Irish Branch at Scotland Yard in March 1883, initially as a small section of the Criminal Investigation Department, to monitor Fenian activity.

In April 1867, the supreme council of the Irish Republican Brotherhood condemns the Clerkenwell Outrage as a “dreadful and deplorable event,” but the organisation returns to bombings in Britain in 1881 to 1885, with the Fenian dynamite campaign.

(Pictured: The House of Detention in Clerkenwell after the bombing as seen from within the prison yard)