General admiral was a Danish, Dutch, German, Russian, Portuguese, Spanish and Swedish naval rank. Its historic origin is a title high military or naval dignitaries of early modern Europe sometimes held, for example the (nominal) commander-in-chief of the Dutch Republic's navy (usually the Prince of Orange).
In the German Kriegsmarine of the Second World War, Generaladmiral was a rank senior to an Admiral, but junior to a Großadmiral. Generaladmiral was a four-star admiral rank, equivalent to a full admiral in the British and American navies. In the traditional German ranking system until World War II, an admiral was equivalent to a British or American vice admiral.
The sleeve insignia for a Generaladmiral was the same as that of a regular admiral, being a thick rank stripe below three regular stripes ( in German naval parlance). Generaladmirals wore a third pip on their shoulder boards to differentiate them from regular admirals. The German Army and Air Force equivalent of Generaladmiral was the rank colonel general (Generaloberst).
In 1943, a directive was issued that should the Oberbefehlshaber der Kriegsmarine ("commander of the navy") hold the rank of Generaladmiral, he would wear the sleeve insignia of a grand admiral, but the shoulder boards of a Generaladmiral.
A similar practice was used in the German Army, allowing colonel generals to wear four pips on the shoulder board when engaged in duties befitting a field marshal.
⇒ see main article Ranks of the Kriegsmarine
The rank of Generaladmiral was first given to the future grand admiral Erich Raeder on 20 April 1936.
Other holders of the rank were: