This study reviews the campaigns and battles of the Sixth Century A. D. Byzantine General Belisarius, attempting to extract common threads of military thought and principles and providing an analysis as to the application of his method to today's military operations. Belisarius won extraordinary victories on three continents, often fighting against overwhelming odds. The study reviews the world environment from the perspective of the Eastern Roman Empire along with the major personalities of the age. After a short review of the Eastern Roman Empire's military structure, the study reviews chronologically, and analyzes Belisarius' campaigns against the Persians, the Vandals, and the Ostrogoths. This study concludes showing that mastership of strategic and tactical thought, deception, psychological warfare, superior technology and training, and elite forces were among the keys of Belisarius success. Finally, these keys of success are related to modern day military operations.