For the Victoria Cross recipient see William Robertson (VC)

Sir William Robert Robertson (1860-1933) was a British field marshal who served as Chief of the Imperial General Staff from 1916 to 1918 during the First World War. Robertson, who began his military career in 1877 as a private, served as Quartermaster General and then as Chief of Staff of the British Expeditionary Force (under John French) before being promoted to CIGS. As CIGS, Robertson was a strong supporter of BEF commander Douglas Haig, and played a major role in the ouster of Prime Minister Herbert Henry Asquith and his replacement with a Tory-dominated coalition led by David Lloyd George. When he was promoted to field marshal in 1920, he became the first man to rise in the British army from the lowest rank (private) to the highest (Field Marshal).