The King traversing the Vimy Ridge. His Majesty King George V, accompanied by General Horne (right), First Army Commander and Lieutenant General Sir Arthur Currie (centre), visit Vimy Ridge after the 9 April 1917 battle. General Henry Sinclair Horne, 1st Baron Horne GCB, KCMG (19 February 1861 – 14 August 1929) was a military officer in the British Army, most notable for his generalship during World War I. He was the only British artillery officer to command an army in the war. Until recently Horne was the unknown General of the Great War and did not have a biographer.