OF-10

A five-star rank is a very senior military rank, first established in the United States in 1944, with a five-star insignia, and corresponding ranks in other countries. The rank is that of the most senior operational military commanders, and within NATO's "standard rank scale" it is designated by the code OF-10.

Not all armed forces have such a rank, and in those that do the actual insignia of the "five-star ranks" may not contain five stars. For example: the insignia for the French OF-10 rank maréchal de France contains 7 stars; the insignia for the Portuguese marechal contains four gold stars; and many of the insignia of the ranks in Commonwealth of Nations contain no stars at all.

Typically, five-star officers hold the rank of general of the army, admiral of the fleet, field marshal, marshal of the air force, general of the air force, and several other similarly named ranks. Five-star ranks are extremely senior - usually the highest ranks. As an active rank, the position exists only in a minority of countries and is usually held by only a very few officers during wartime. In times of peace, it is usually held only as an honorary rank.

Despite the rarity and seniority of five-star officers, even more senior ranks have been adopted in the United States, namely, admiral of the navy and general of the armies. Other names for highly senior ranks from the twentieth century include généralissime (France), generalisimo (Spain) and generalissimus (USSR).

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