Interest in the European project has waned since Ireland voted to join the economic community three decades ago on a wave of enthusiasm.
The 71 per cent turnout in the May 1972 poll was the biggest for a referendum since the vote on the Constitution itself in 1937. The Yes vote was even more impressive.
An informal coalition of Fianna Fail, Fine Gael and the farming organisations led the drive for EEC entry, but voter support extended beyond even those in a crushing five-to-one defeat for the No campaign.
Opposition had come mainly from Labour and the trade unions, with nationalist groups including Sinn Fein also against. The War of Independence veteran, Gen Tom Barry, said he would be reluctant to call anyone who voted for entry a "traitor", but he urged people to honour the State's founding fathers and "keep us out of the cesspool of Europe".
The ATGWU accused RTE of bias during the campaign, alleging that a number of programmes, including the radio serial The Kennedys of Castle ross, were featuring subtle proEEC messages. After the vote, Dr Conor Cruise O'Brien of Labour said his party would work "to prevent the worst effects of membership".
The 1987 referendum on the Single European Act was marked by a dramatically reduced turnout, a mere 44 per cent. The poll had been forced on the government by a constitutional challenge to the Act by an economist, Mr Raymond Crotty, who claimed vindication despite the 70 per cent Yes vote. Given the turnout, this represented only one-third of the electorate, he said.
The main political leaders supported the SEA, while the Workers' Party, the Greens and Sinn Fein were among those opposed. The Sinn Fein president, Mr Gerry Adams, called the Yes campaign "an unholy alliance" with "Margaret Thatcher, Brussels bureaucrats and supporters of NATO". But Mr John Hume of the SDLP said the creation of the single European market meant the Border would disappear "as a fiscal entity", and any other result would have been disastrous for Ireland.
The Maastricht referendum campaign in June 1992 divided on similar lines. It was also a dry run for the autumn votes on abortion, however, so antiabortion campaigners were prominent in a No campaign. Turnout was 57.3 per cent.
The Democratic Left leader, Proinsias De Rossa, warned that the "flawed" treaty would take us "more than halfway" to a common defence policy; while the Greens dubbed the eventual 69 per cent Yes vote "a victory for the gombeen mentality that spans the political spectrum from the PDs to Labour".
Despite being held the same day as the poll on the Belfast Agreement, the 1998 referendum on the Amsterdam Treaty drew only a 56 per cent turnout. The EU commissioner, Mr Padraig Flynn, wrote in The Irish Times that, unlike the earlier European votes, there was no "grand project" in the treaty. But then, as in the latest campaign, the Greens accused the government of rushing the vote.
Also campaigning against Amsterdam, Sinn Fein said the decision to hold the two polls on the same day was "inexcusable". But the Yes campaign this time included Democratic Left, whose leader, Proinsias De Rossa, characterised the opposition as a "strange alliance", ranging from wealthy businessmen to extreme nationalists. The treaty was approved, but the No vote topped 38 per cent, the highest to date.
