The aim of this work is to examine the evolution and role of the U.V.F. in Ulster from 1912-4. In the opening chapter the sectarianism that plagued Ulster during the Home Rule crisis is discussed. The work focuses on Castledawson in Londonderry, where an alleged attack by Hibernians against Presbyterian school children sparked riots in Belfast and resulted in Catholics being driven from their jobs. This work shows how the emerging importance of public opinion forced the Unionist leadership to reign in the militant excesses of some Unionists. The chapter discusses the damage inflicted upon the Unionist campaign of opposition to Home Rule by the Belfast riots, with some papers describing Unionists working in the Haarland and Wolff shipyards as terrorists. In chapter two the formation and structure of the U.V.F. in Belfast, Antrim, and Fermanagh is examined. The chapter discusses the military structure of the U.V.F. and why the organisation was better suited to urban Ulster. In the course of the chapter the link between big business and the U.V.F. is examined, the focus of which is on George Clark of Workman and Clark shipyards. The difference in political views of those on the U.U.C. is studied to show who was in favour of compromise, and who wished to fight. The role of the U.V.F. in halting sectarian attacks in both rural and urban Ulster is discussed, and the levels of recruitment to the organisation in Belfast, Antrim, and Fermanagh. In the final chapter three major issues that affected Ulster in 1914 are examined. The failure of Asquith to offer a realistic settlement to Carson in the autumn of 1913-4 undermined Carson’s authority as leader of the U.U.C. The radical line pursued by some members of government and a significant minority of the Unionist party during the coercion crisis and the Lame gunrunning is examined, to show the effect this had on the political process. Lastly the renewal of sectarian attacks in Ulster as moderate Unionism was marginalised is discussed to show the danger of some form of conflict breaking out if Home Rule was forced on Unionists.