Reichsführer-SS (German: [ˈʁaɪçsˌfyːʁɐ ˈɛs ˈɛs] (listen), lit. "Reich Leader-SS") was a special title and rank that existed between the years of 1925 and 1945 for the commander of the Schutzstaffel (SS). Reichsführer-SS was a title from 1925 to 1933, and from 1934 to 1945 it was the highest rank of the SS. The longest serving and most noteworthy Reichsführer-SS was Heinrich Himmler.