The Provisional IRA
Paramilitary groups had now begun to operate on both sides of the sectarian divide, while civil rights marches became increasingly prone to confrontation.
More problematic still, the Orange Order's marching season had begun. Following the annual Apprentice Boys' march in August 1969, civil unrest in Belfast became a three-day explosion of nationalist rioting in Derry.
The so-called 'Battle of Bogside' only ended with the arrival of a small body of British troops at the request of Chichester Clark - a significant acknowledgement that the government of Northern Ireland was fast losing its grip on security.
'The more militant 'Provisional' IRA demanded the unification of Ireland in defiance of Britain and was prepared to use violence to achieve it.'
A political response came in the shape of the joint 'Downing Street Declaration' by Chichester-Clark and the British prime minister Harold Wilson. Once again, the British government had intervened to force the pace of reform.
The declaration sought to placate both communities by stating its support for equality and freedom from discrimination, while reasserting that Northern Ireland would remain part of the UK as long as that was the will of the majority of its people.
A blizzard of reforms then followed, including the setting up of a variety of bodies to allocate council housing, investigate the recent cycle of violence and review policing. The latter recommended the disbanding of the hated 'B Specials' auxiliaries, the disarming of the police and the setting up of the Ulster Defence Regiment under the control of the British Army.
Outraged loyalists responded with yet more civil unrest and violence. Attacks on Catholic areas escalated, and many homes were burned.
The IRA - one of whose stated aims was the defence of the Catholic minority - had remained largely inactive during this period. It had abandoned its last campaign of violence in 1962, having been successfully contained by internment and other counter-measures.
In late 1969, the more militant 'Provisional' IRA (PIRA) broke away from the 'Official' IRA. Like the Official IRA, the PIRA supported civil rights, the defence of the Catholic community and the unification of Ireland. But in contrast it was prepared to pursue unification in defiance of Britain and would use violence to achieve its aims.
At the same time, loyalist paramilitaries were also organising. The UVF was joined by the Ulster Defence Association, created in 1971, which rapidly expanded to a membership of tens of thousands, but somehow avoided being banned.
In the middle was the British Army. Its various attempts to control the PIRA, such as house-to-house searches and the imposition of a limited curfew, only served to drive more recruits into the ranks of the paramilitaries.