In June 1602, English forces under Sir George Carew laid siege to Dunboy Castle on the Beara Peninsula in County Cork, a stronghold of the O'Sullivan Beare clan. The castle fell after a fierce bombardment, and the surviving defenders were executed. The fall of Dunboy marked the effective end of Gaelic resistance in Munster and was a final blow to the Spanish-backed Irish cause in the Nine Years' War.

The Siege of Dunboy is a powerful subject in the poetry of the O'Sullivan Beare clan, which lamented the fall of their ancestral seat and the destruction of their power. The siege is remembered in later nationalist poetry as a symbol of the brutal suppression of Gaelic Ireland. Its memory was invoked by poets of the Gaelic Revival, who saw in the fall of Dunboy a microcosm of the larger tragedy of Irish history.