The Commander In Chief of the Pacific Fleet during World War II was the Admiral Chester Nimitz.
Ten days after the attack on Pearl Harbor on December 7, 1941, he was selected commander-in-chief of the Pacific North American fleet (CINCPAC), and his rank of Admiral became effective as of December 31. Although he was appointed to the post in the most critical period of the Pacific War, Major Nimitz managed to successfully organize his forces to stop the Japanese attack, despite having been defeated and having suffered numerous losses of ships and airplanes.
