 In the late 1960s , nationalist grievances were aired publicly in mass civil rights protests , which were often confronted by loyalist counter @-@ protests . The government 's reaction to confrontations was seen to be one @-@ sided and heavy @-@ handed in favour of unionists . Law and order broke down as unrest and inter @-@ communal violence increased . The Northern Ireland government requested the British Army to aid the police , who were exhausted after several nights of serious rioting . In 1969 , the paramilitary Provisional IRA , which favoured the creation of a united Ireland , emerged from a split in the Irish Republican Army and began a campaign against what it called the " British occupation of the six counties " . 
