Louis Mountbatten traveled to the United States to assume command of HMS Illustrious during the period of the Atlantic Charter. However, his tenure was abruptly interrupted by his new role as Adviser on Combined Operations, succeeding Admiral Keyes. In this capacity, he played a significant role in various operations, including the commando raids on Vaagso and St Nazaire. Subsequently, he was promoted to Chief of Combined Operations, attaining the rank of acting Vice Admiral, as well as being honored with the titles of Honorary Lieutenant General and Honorary Air Marshal.
Following the United States' entry into the war, there was a strong push for an early offensive, which led to the establishment of the combined Chiefs of Staff. During this time, Mountbatten developed a friendship with General Marshall, contributing to the alleviation of tensions among the Allied forces. The lessons learned from the Dieppe raid proved invaluable, paving the way for the North African landings in November 1942, known as Operation Torch. Mountbatten participated in the Casablanca conference and was later appointed as Supreme Allied Commander for Southeast Asia during the Quebec conference.
