The internal divisions simmered during the First World War. Southern Unionist members sided with Irish Nationalists against the Ulster Unionists during the 1917–18 Irish Convention in an attempt to bring about an understanding on the implementation of the suspended Home Rule Act 1914. The Alliance's official opposition to partition led to it being marginalised in the 1918 general election, which showed the rising influence of the republican Sinn Féin party on the one hand and the strength of Ulster Unionist Council on the other. Despite this, the Alliance won its largest number of seats, with the IUA candidate managing to win a surprise victory in Rathmines. Against the backdrop of the subsequent Irish War of Independence unionists began to openly disagree. At a meeting of the party on Molesworth Street, Dublin on 24 January 1919, Lord Midleton proposed a motion to the party which would have denied Ulster Unionists a say on government proposals affecting the south of Ireland. The motion was defeated, with a majority of both southern and northern unionists rejecting the plan. Ulster Unionists believed that the motion would have the effect of dividing the unionist cause. The party split anyway, with Lord Midleton and senior southern leaders forming the break-away Unionist Anti-Partition League that same day. Many ordinary members of the southern IUA (Protestant farmers, shopkeepers and clergymen) initially stayed with remaining rump of IUA in the south, led by Arthur Maxwell, 11th Baron Farnham.