Complex sentence: Upon graduation in June 1924, Major Richardson sailed for France to attend the Ecole Superieure de Guerre, Paris, and upon graduation on September 2,1926, he was ordered to Rome, Italy to serve as Military Attaché.
Split into simpler sentences: Upon graduation in June 1924, Major Richardson sailed for France to attend the Ecole Superieure de Guerre, Paris and upon graduation on September 2. He was ordered to Rome, Italy to serve as Military Attaché.