a Syracusan, son of Hipparitus, famous for his power and abilities. He was related to Dionysius, and often advised him, together with the philosopher Plato, who at his request had come to reside at the tyrant's court, to lay aside the supreme power. His great popularity rendered him odious in the eyes of the tyrant, who banished him to Greece. There he collected a numerous force, and resolved to free his country from tyranny. This he easily effected on account of his uncommon popularity. He entered the port of Syracuse only in two ships; and in three days reduced under his power an empire which had already subsisted for 50 years, and which was guarded by 500 ships of war, and above 100,000 troops. The tyrant fled to Corinth, and Dion kept the power in his own hands, fearful of the aspiring ambition of some of the friends of Dionysius; but he was shamefully betrayed and murdered by one of his familiar friends called Callicrates or Callipus, 354 years before the Christian era.

DION Cassius, a native of Nicæa in Bithynia. His father's name was Apronianus. He was raised to the greatest offices of state in the Roman empire by Pertinax, and his three successors. He was naturally fond of study, and he improved himself by unwearyed application. He was ten years in collecting materials for a history of Rome, which he made public in 80 books, after a laborious employment of 12 years in composing it. This valuable history began with the arrival of Æneas in Italy, down to the reign of the emperor Alexander Severus. The first 34 books are totally lost, the 20 following, that is, from the 35th to the 54th, remain entire, the fix following are mutilated, and fragments is all that we possess of the last 20. In the compilation of this extensive history, Dion proposed to himself Thucydides for a model, but he is not perfectly happy in his imitation. His style is pure and elegant, and his narrations are judiciously managed, and his reflections learned: but upon the whole, he is credulous, and the bigotted slave of partiality, satire, and flattery. He inveighs against the republican principles of Brutus and Cicero, and extols the cause of Caesar. Seneca is the object of his satire, and he represents him as debauched and licentious in his morals.