Burning Of The Custom House
By 1921 most of the IRA attacks on the British forces in Dublin consisted either of assassinations of selected police, military or administration figures by the Squad, or ambushes by one of the four Active Service Units of the IRA's Dublin Brigade.
These were usually rapid and fleeting attacks using grenades and handguns, followed by a quick getaway, but not everyone on the Republican side agreed with these tactics.
At an Irish cabinet meeting held on May 21st 1921, President of the Republic, Éamon de Valera, called for a spectacular public show of force by the IRA, to reinforce the idea that it was an army representing an Irish Government.
Michael Collins was very much against this type of attack, but he was overruled, it was decided to attack and burn the Custom House, which, although an important government building, was not defended by the British military.
In the early afternoon of May 25th 1921, roughly 120 non-uniformed IRA Volunteers began to gather around the Custom House in groups of twos and threes. They were armed only with pistols and a limited amount of ammunition.
At 1 pm, they rushed the Custom House and overpowered the police guard. A lorry pulled-up outside the building with tins of petrol and bales of cotton, which were then sprinkled throughout the building.
The IRA Volunteers herded all the staff into the main hall. The caretaker of the building was shot dead when he tried to call the police.
At about 1:10 pm, a watching policeman notified British forces, 60 Auxiliaries in three lorries and an armoured car quickly arrived on the scene. IRA Volunteers from the 1st, 3rd and 4th battalions were positioned outside the building to stop the enemy from approaching.
Four Auxiliaries were wounded in a gun battle with one of these IRA protection teams outside the building. Other Auxiliaries fired into the building with rifles and Lewis machine guns, exchanging fire with the IRA fighters inside.
Some IRA Volunteers and civilians were killed or wounded by the Auxiliaries. As fighting raged outside, IRA Volunteers inside the building were ordered to set it alight.
The ammunition of the IRA Volunteers quickly ran out; the firefight ended within 30 minutes. Some Volunteers were shot as they tried to run away.
Many others were arrested along with civilians as they came out of the now burning Custom House with their hands up. The Fire Brigade, which had been delayed from responding by other IRA companies in the city, arrived too late to put out the fire.
British military forces composed of units from the Wiltshire Regiment arrived and took over the operation from the Auxiliaries at this point. A total of 111 people were arrested, of whom 70–80 were IRA members.
The Custom House burned for five days and was all but destroyed by the fire. With it were destroyed many centuries of local government records.
From the Republican point of view, the operation was successful for its propaganda value, but it was a heavy blow in terms of the numbers lost, both killed and arrested.