Several hundred IRA men from the Dublin Brigade occupied and burned the Custom House

The biggest single loss for the IRA, however, came in Dublin. On 25 May 1921, several hundred IRA men from the Dublin Brigade occupied and burned the Custom House (the center of local government in Ireland) in Dublin city center. Symbolically, this was intended to show that British rule in Ireland was untenable. However, from a military point of view, it was a heavy defeat in which five IRA men were killed and over eighty captured.