Ireland was deeply scarred by religious sectarianism following the Protestant Reformation as tensions between the native Catholic Irish and Protestant settlers from Britain led to massacres and attempts at ethnic cleaning by both sides during the Irish Rebellion of 1641 , Cromwellian conquest of Ireland , Irish Rebellion of 1798 and the Home Rule Crisis of 1912 . The invasion of Ireland by English parliamentarian forces under Oliver Cromwell in 1659 was notoriously brutal and witnessed the widespread ethnic cleansing of the native Irish . The failure of the Rebellion of 1798 , which sought to unite Protestants and Catholics for an independent Ireland , helped cause more sectarian violence in the island , most infamously the Scullabogue Barn massacre , in which Protestants were burned alive in County Wexford . The British response , which included the public executions of dozens of suspected rebels in Dunlavin and Carnew , along with other violence perpetrated by all sides , ended the hope that Protestants and Catholics could work together for Ireland
Scullabogue Barn massacre
Scullabogue Barn massacre
Sectarianism