The Republican ideal of a non-sectarian society was greatly damaged by sectarian atrocities committed by both sides during the rebellion . The British response was swift and harsh : days after the outbreak of the rebellion local forces publicly executed suspected United Irishmen in Dunlavin and Carnew . Government troops and militia targeted Catholics in general and the rebels on several occasions killed Protestant loyalist civilians . In Ulster , the 1790s were marked by naked sectarian strife between Catholic Defenders and Protestant groups like the Peep O'Day Boys and the newly founded Orange Order
Carnew .
Carnew executions
History of Ireland (1691–1800)