Generalissimo

Francisco Franco, Generalissimo of Spain
Francisco Franco, Generalissimo of Spain from 1936 to 1975

Proposed insignia of the Generalissimus of USSR, (only held by Joseph Stalin)
Proposed insignia of the Generalissimo of the Soviet Union (only held by Joseph Stalin)

Generalissimo (/ˌdʒɛn(ə)rəˈlɪsɪmoʊ/ JEN-(ə-)rə-LIS-ih-moh), also generalissimus, is a military rank of the highest degree, superior to field marshal and other five-star ranks in the states where they are used.