Gensui (Imperial Japanese Navy)

Kaigun-gensui (海軍元帥, Grand admiral), formal rank designations: Gensui-kaigun-taishō (元帥海軍大将, Marshal-admiral) was the highest rank in the prewar Imperial Japanese Navy. The term gensui was used for both the navy and the Imperial Japanese Army, and was a largely honorific title awarded for extremely meritorious service to the Emperor. In the Meiji period, the title was awarded to five generals and three admirals. In the Taishō period it was awarded to six generals and six admirals, and in the Shōwa period it was awarded to six generals and four admirals. Equivalent to a five-star rank (OF-10), it is similar to Admiral of the Fleet in the UK Royal Navy and Fleet admiral in the United States Navy.

Kaigun-gensui 海軍元帥
Gensui Badge
Country	Japanese Empire
Service branch	Imperial Japanese Navy
Rank	Five-star
NATO rank code	OF-10
Formation	20 January 1898
Abolished	1945
Next higher rank	Dai-gensui
Next lower rank	Admiral
Equivalent ranks	Gensui (Army)

Note that several were promoted the same year they died; these were posthumous promotions.