Field-Marshal Sir Claud William Jacob, GCB, GCSI, KCMG (21 November 1863 – 2 June 1948) was a British Army officer. He served in the Second Boer War and the subsequent East Africa Campaign. He went on to serve in the First World War as commander of the Dehra Dun Brigade, as General Officer Commanding 21st Division and as General Officer Commanding II Corps in the Fifth Army. During the Battle of the Somme, his corps undertook the British attack during the Battle of Thiepval Ridge in September 1916 and the subsequent assault on St Pierre Divion during the Battle of the Ancre in November 1916. He remained in command of II Corps for the Battle of Passchendaele in Autumn 1917. After the War he commanded a corps of the British Army of the Rhine during the occupation there and then served as Chi