Carson’s role as the leader of Ulster unionism during the Home Rule crisis only served to accelerate an already rapid rise in British politics. The unity of Ulster unionism and the British Conservative Party before the Great War, as well as Carson’s control of the Ulster Volunteer Force—which ultimately converted into the 36th (Ulster) Division during the war—meant that his stock was never higher than during the early war years. This coincided with the zenith of Carson’s power in British politics, as he played a major role in bringing down Asquith’s wartime coalition government in late 1916. In the replacement coalition, according to Winston Churchill, ‘Mr Lloyd George, Mr Bonar Law and Sir Edward Carson assumed, with what were in practice dictatorial powers, the direction of affairs’.
Carson was a member of the cabinet from May 1915 until his resignation in January 1918, by which time, J.C. Beckett has argued, ‘he was on the fringe of British politics rather than in the centre’. This transformation occurred for a number of reasons, not least because Lloyd George deceived him over the Irish Question and then replaced him in 1917 after an unsuccessful period as first lord of the admiralty.