Field-Marshal Sir William Robertson, Britain's first Field-Marshal to advance from the ranks, served as Chief of the Imperial General Staff from December 1915 to February 1918. Both his powers and responsibilities were without precedent in British military annals. Given virtual autonomy within the War Office, he served as the supreme strategic advisor to the government during the planning and execution of the controversial Somme and Passchendaele offensives, nbattles the scale and violence of which were unparalleled in British history. Particular care has been devoted to Robertson's private and secret communication with political leaders, the king, newspaper proprietors and editors, and his fellow senior officers. Robertson's numerous communications with Haig, which constitute a substantial part of his correspondence, are very revealing of his relationship with the Commander-in-Chief of the BEF. The letters and telegrams in this volume are enlightening also on the often bitter conflicts between the civil and military authorities over manpower questions, the coordination of Allied military planning, and British grand strategy. That Robertson's private views of his civilian superiors are reflected in his correspondence were extremely censorious is not surprising, given the mutual distrust and hostility that usually existed between British politicians, especially Lloyd George and his supporters, and senior army officers...