100 years on, the party seems torn between the challenges of recouping 'traditional' votes and staking out the ground of civic unionism, writes Graham Walker.
The Ulster Unionist Party (UUP) can claim to be the oldest political party on the island of Ireland. This week marks the centenary of the formation of the Ulster Unionist Council (UUC), the body which remains at the heart of the party's structure.
The UUC was designed to meet a perceived political need. It was a central co-ordinating organisation that imposed a renewed sense of discipline and direction on the anti-Home Rule movement of the period. At the beginning of the 20th century unionist unity, always brittle, looked set to come apart in a political context in which the Home Rule threat had apparently receded. Class tensions, particularly around the land question, simmered.
The UUC had the effect largely of bringing Ulster unionists back together, and its emergence also reflected the extent to which the anti-nationalist cause had become identified with Protestant Ulster.
Those behind the initiative were younger, middle-class politicians impatient with the patrician leadership of Col Edward Saunderson. They wanted a political "machine" that would mobilise constituency associations and involve them purposefully in the organisation. Thus half of the membership of the UUC was drawn from the constituencies.
In addition, the Orange Order was formally represented, something which continues to this day and is the cause of much internal unionist debate.
The incorporation of the order proved a historic and fateful decision: it was a signal that Ulster unionism was willing to identify with Protestant exclusivism. Tensions between this ethnic tendency and civic and inclusive forms of unionist argument were to characterise the party throughout its history.
The practical management of the UUC was undertaken by a standing committee the composition of which brought together the conservative and liberal unionist strands of Ulster unionism, and the manufacturing and commercial as well as landed economic interests. Labour interests would be represented from 1918.
By the time the Liberal government brought forward its Home Rule Bill in 1912, the Ulster unionists had gelled into a formidable protest movement, led now by Edward Carson. A singular feature of Irish and British politics from this point to partition in 1921 was the reinvention of the Dubliner Carson into an honorary Ulsterman, moulded by James Craig into unionism's belated answer to Parnell.
However, Carson declined the opportunity of becoming prime minister of the new Northern Ireland, and passed the unionist leadership to Craig.
The latter eschewed the histrionics of the campaign against Home Rule and displayed the pragmatism necessary for the business of governing the devolved entity, a task the unionists would carry out for half a century.
In government, the Unionist Party gave priority to its own internal unity and the maintenance of its tribal base of support among the majority Protestant population.
Although Craig and his successors, Andrews and Brooke, adopted a minimalist approach to devolution, the impression was given to supporters that the government was more in control of Northern Ireland's destiny than eventually turned out to be the case. The expectations of the party's grassroots, so long allowed to grow, were difficult to bring down to reality when London finally insisted on reforms.
Unionist prime ministers and cabinets often found themselves caught between the demands of government and the pressures exerted on them from within the party. The UUC's central role was reflected in the way it conducted periodic reorganisation; however, no constitution for the party, as opposed to the council, was produced, and anachronisms from the early battles over Home Rule abounded.
The latitude accorded to local associations also had the effect of rendering the party a collection of small localised groupings which the Belfast headquarters struggled to manage.
It was the stubborn refusal of some associations to comply with the direction favoured by Terence O'Neill which helped undo his premiership during the 1960s.
The continuing influence of the Orange Order on the party's ruling councils also contributed significantly. As the political crisis enveloped Northern Ireland from 1968 the cumbersome structure and outdated mode of operation of the Unionist Party inhibited an effective response from the government, especially during the short premiership of Chichester-Clark. Calls for modernisation, and the breaking of the Orange link, came from moderates; others deplored moves towards greater centralisation as attempts to stifle the people's voice.
The party endured the turmoil of the 1970s and 1980s, involving splits, breakaways, and the electoral challenge of Paisley's DUP. Through it all it remained the main political voice of the pro-union community. Its "broad church" character enabled it to contain ideological and policy divisions such as that over devolution and integration.
However, the party's role in the peace process from the late 1990s was to push its capacity for accommodation and absorption to the limit.
Moreover, the party's rituals and structures again became a significant factor in political developments with the leader, David Trimble, having repeatedly to acquire the backing of specially convened UUC meetings.
The peculiarities of the Unionist Party, not least the presence in the UUC of individuals who supported other parties, were laid bare as Trimble won sufficient votes to hang on to his position.
Since relinquishing the title of the leading unionist party to the DUP in 2003, the Unionist Party has not effectively pursued internal reform.
The Orange connection remains and no credible attempt has been made to win Catholic votes. There are many progressive voices in the party, and its centenary ought to be an occasion to recall impressive forgotten figures from its history: Thomas Sinclair, JM Andrews, Edmund Warnock, Harry Midgley, Montgomery Hyde, Dehra Parker, Brian Maginess, Roy Bradford, Harold McCusker.
Nevertheless, the party has still not transcended the communal confines of its origins, and currently seems torn between the challenges of recouping "traditional" votes from the DUP and staking out the ground of civic unionism.
• Graham Walker is author of A History of the Ulster Unionist Party: Protest, Pragmatism and Pessimism (Manchester University Press, 2004)