After being told by his congressman that all available appointments to West Point were already spoken for, Nimitz was appointed to the United States Naval Academy from Texas's 12th congressional district in 1901. He graduated with distinction on 30 January 1905, seventh in a class of 114.

Under his command, the destroyer Decatur ran aground on a sand bar in the Philippines on 7 July 1908. The ship was pulled free the next day, and Nimitz was court-martialed, found guilty of neglect of duty, and issued a letter of reprimand.

Ten days after the attack on Pearl Harbor on 7 December 1941, he was selected as commander in chief, United States Pacific Fleet (CINCPACFLT), with the rank of admiral, effective 31 December. He took command in a ceremony on the top deck of the submarine USS Grayling (SS-209).

He played a major role in the naval history of World War II as Commander in Chief, United States Pacific Fleet (CinCPac)

On 2 September 1945, Nimitz signed for the United States when Japan formally surrendered on board the Missouri in Tokyo Bay.
He was the United States' last surviving officer who served in the rank of fleet admiral.

USS Nimitz, the first of her class of ten nuclear-powered supercarriers, was commissioned in 1975