John Joseph "Black Jack" Pershing GCB (September 13, 1860 – July 15, 1948) was an officer in the United States Army. Pershing is the only person, while still alive, to rise to the highest rank ever held in the United States Army—General of the Armies—equivalent only to the posthumous rank of George Washington. Pershing led the American Expeditionary Force in World War I and was regarded as a mentor by the generation of American generals who led the United States Army in Europe during World War II, including George C. Marshall, Dwight D. Eisenhower, Omar Bradley and George S. Patton.