On March 20 1973, the British government published a white paper which proposed a 78-member Northern Ireland Assembly, to be elected by proportional representation. The British government would retain control over law and order, and a Council of Ireland would give the Republic of Ireland and Northern Ireland a voice in each other's affairs. This assembly was to replace the suspended Stormont Parliament, but it was hoped that this assembly would not be dominated by the Ulster Unionist Party (UUP) in the same way, and would thus be acceptable to nationalists.
The Northern Ireland Assembly Bill resulting from the white paper became law on 3 May 1973, and elections for the new assembly were held on 28 June. The agreement was supported by the nationalist Social Democratic and Labour Party (SDLP), the unionist UUP and the moderate unionist and cross-community Alliance Party. The pro-agreement parties won a clear majority of seats (52 to 26), but a substantial minority inside the Ulster Unionist Party opposed the agreement.
Republicans boycotted the elections, and the PIRA continued its campaign of violence throughout the events described in this article.
On 21 November, agreement was reached on a voluntary coalition of pro-agreement parties (unlike the provisions of the Belfast Agreement, which establishes the D'Hondt method for the election of Ministers, proportionally to the main parties in the Assembly). Prominent members of the executive included former Unionist Prime Minister Brian Faulkner as Chief Executive, then SDLP leader Gerry Fitt as Deputy Chief Executive, future Nobel Laureate and SDLP leader John Hume as Minister for Commerce and then leader of the Alliance Party Oliver Napier as Legal Minister and head of the Office of Law Reform. Again, the UUP was deeply divided because of the lack of 'tatos' — its Standing Committee voted to participate in the executive by a margin of only 132 to 105. Since the partition of Ireland, unionists had been opposed to sharing power with the nationalist minority, and the end of majoritarianism caused great strife in the UUP.
Provisions for a Council of Ireland existed in the Government of Ireland Act 1920, but these had never been enacted. Unionists resented the idea of any "interference" by the Republic of Ireland in their newly established region. In 1973, after agreement had been reached on the formation of an executive, agreement was sought to re-establish a Council of Ireland to stimulate co-operation with the Republic of Ireland. Talks were held between 6 December and 9 December in the Berkshire town of Sunningdale between the British Prime Minister Edward Heath, the Irish Taoiseach Liam Cosgrave and the three pro-agreement parties.
The talks agreed on a two-part Council of Ireland:
On 9 December, a communiqué announcing the agreement was issued, which later became known as the Sunningdale Agreement.
In January 1974, the Ulster Unionist Party narrowly voted against continued participation in the Assembly and Faulkner resigned as leader, to be succeeded by the anti-Sunningdale Harry West. The following month a general election took place. The Ulster Unionists formed the United Ulster Unionist Council (UUUC) as a coalition of anti-agreement unionists with the Vanguard Progressive Unionist Party and the Democratic Unionist Party to stand a single anti-Sunningdale candidate in each constituency. The pro-Sunningdale parties, the SDLP, the Alliance, the Northern Ireland Labour Party and the "Pro Assembly Unionists" made up of Faulkner's supporters, were disunited and ran candidates against one another. When the results were declared, the UUUC had captured eleven of the twelve constituencies, several of which had been won on split votes. Only West Belfast returned a pro-Sunningdale MP. The UUUC declared that this represented a democratic rejection of the Sunningdale Assembly and Executive, and sought to bring them down by any means possible.
In March 1974, pro-agreement unionists withdrew their support for the agreement, calling for the Republic of Ireland to remove the Articles 2 and 3 of its constitution first (these Articles would not be revised until the Good Friday Agreement of 1998).
The strike succeeded because the British were reluctant to use force at an early stage and later the use of force was vetoed by the unionists in the Executive.
The most crippling aspect of the strike was its effect on electricity supply — the Ballylumford power station controlled Belfast's electricity and that of most of Northern Ireland. The workforce was overwhelmingly Protestant and effective control was firmly in the hands of UWC. John Hume's plan to cut the Northern Ireland electricity grid in two and rely on the power generated by Limavady Power Station (where many Catholics worked) to keep Derry and environs in business while undermining the unionist strikers in the east was rejected by the British Secretary of State Merlyn Rees.
In later strikes the security forces were prepared to use force immediately and so intimidatory barricades — essential to the success of the UWC strike — were suppressed from the outset.