Fleet Admiral

An Admiral of the Fleet, or Fleet Admiral (元帥, gensui), is a military naval officer of the highest rank.

The rank of Fleet Admiral has been reserved for wartime use only, the last of which were in World War II. It is usually a rank ranking above Admiral. The rank is often held by the most senior Admiral of an entire naval service but is also a generic term for a senior Admiral in command of a large group of ships, comprising a fleet or, in some cases, a group of fleets.

If actually a rank (equivalent to an Army Field Marshal or General of the Army, which ranks above General), its name varies depending on the country, including Fleet Admiral, Admiral of the Fleet, Admiral of the Navy, and Grand Admiral. (In some navies, however, such as the German Kriegsmarine during World War II, "Admiral of the Navy" has been considered an even higher rank than Admiral of the Fleet or its equivalent.)

It ranks above Vice Admiral, Rear Admiral and usually full Admiral, and is usually given to a senior Admiral commanding multiple fleets as opposed to just one fleet.

The title Admiral of the Fleet can trace its origins to the Middle Ages, where the title was typically granted to a nobleman who was appointed by a monarch to raise and command a navy for a specific campaign.

The only Fleet Admirals seen so far in One Piece is the current one, Sengoku, and Kong seen 20 years ago. They, alongside with the Admirals, are the only ones within the Marine capable of initiating a Buster Call, as well as grant World Government agents the right to do so.