Field Marshal Sir William Robert Robertson, 1st Baronet, GCB, GCMG, GCVO, DSO (29 January 1860 – 12 February 1933) was a British Army officer who served as Chief of the Imperial General Staff (CIGS) – the professional head of the British Army – from 1916 to 1918 during the First World War. As CIGS he was committed to a Western Front strategy focusing on Germany and was against what he saw as peripheral operations on other fronts. While CIGS, Robertson had increasingly poor relations with David Lloyd George, Secretary of State for War and then Prime Minister, and threatened resignation at Lloyd George's attempt to subordinate the British forces to the French Commander-in-Chief, Robert Nivelle. In 1917 Robertson supported the continuation of the Battle of Passchendaele (also known as the Thi