On December 17, 1985, all fifteen Ulster Unionist Members of Parliament resigned their seats in the House of Commons. This mass resignation was a direct protest against the Anglo-Irish Agreement, which had been signed by the British and Irish governments a month earlier. The agreement aimed to give the Republic of Ireland a consultative role in the governance of Northern Ireland, a move deeply opposed by Unionists who viewed it as an infringement on British sovereignty and a step towards a united Ireland. The resignations triggered by-elections, which Unionists hoped would serve as a referendum on the agreement.
