After a two-year interim period in which Lieutenant General Count Franz Wimpffen commanded the Navy, in September 1854 Emperor Franz Joseph I promoted his younger brother, Archduke Ferdinand Maximilian (commonly referred to as Ferdinand Max), to the rank of Rear Admiral and named him Commander-in-Chief of the Austrian Navy. At the age of 22, Ferdinand Max became the youngest "Oberkommandant" in the history of the Austrian Navy, being a year younger than when Archduke Friedrich of Austria assumed command of the navy ten years earlier.