Edward Ian Claud Jacob was born in Quetta, Pakistan on 27 September 1899 the son of Field Marshal Sir Claud Jacob and Clara Wyatt. In 1924 he married Cecil Bisset Treherne (died 1991) and they had two sons. He was knighted in 1960 and was also a Honorary Lieutenant-General.

He joined the Royal Engineers in 1918 and was made Lieutenant-Colonel in 1939. He was Military Assistant Secretary of the Committee of Imperial Defence, 1938 and Military Assistant... Secretary to the War Cabinet, 1939-46. In 1940 he was promoted to Lieutenant Colonel but his application to return to regimental duty was denied in the national interest. In 1941 he accompanied Winston Churchill to two meetings with President Roosevelt - the Atlantic meetings aboard HMS Prince of Wales in August and aboard HMS Duke of York in December. In 1942 he accompanied Churchill on tours of the Middle East and Turkey, Cyprus & Tripoli, he also organised the Churchill/Roosevelt talks in Casablanca. In 1943 he accompanied Churchill to the Second Washington Conference and to the First Quebec Conference as well as to the Italian Front & to Moscow. In 1945 he attended the Yalta and Potsdam Conferences. He also accompanied Prime Minister Attlee to the USA and Canada and the Foreign Secretary Bevin to Moscow. He was the British Military Adviser at the United Nations Conference in San Francisco. In 1946 he attended the War Crimes Trial at Nuremberg and was Military Adviser to the Stansgate Commission in Cairo. He retired from the army and was made an Honorary Major General. He became Controller of European Services at the BBC in 1946, then BBC Director of Overseas Services in 1947 (he was on leave of absence during 1952) and was Director-General of the BBC, 1952-1960. During 1952 he was Chief Staff Officer to the Minister of Defence and Deputy Secretary of the Cabinet. He was a Trustee of the Imperial War Museum, 1966-1973. He was a Suffolk County Councillor in 1960-70 and 1974-77, a JP in Suffolk, 1961-1969, and was Deputy Lieutenant of Suffolk, 1964-1984. Jacob died on 24 April 1993.