noun. Roman Emperor who when faced with military problems decided in 286 to divide the Roman Empire between himself in the east and Maximian in the west; he initiated the last persecution of the Christians in 303 (245-313).
noun. Emperor of Rome; nephew and son-in-law and adoptive son of Antonius Pius; Stoic philosopher; the decline of the Roman Empire began under Marcus Aurelius (121-180).
noun. Roman Emperor who succeeded Tiberius and whose uncontrolled passions resulted in manifest insanity; noted for his cruelty and tyranny; was assassinated (12-41).