HIERON II., king of Syracuse, born at the close of the fourth century B.C., was descended from Gelon. He distinguished himself as a soldier, and in a popular tumult was chosen general by the Syracusan army. He not only got this appointment confirmed by the people themselves, but having married the daughter of Leptines, the most influential man in Syracuse, the way was open to still higher power. Not feeling secure with the fickle mercenaries who had elected him, he took occasion to expose them to be cut to pieces by the Mamertines; then levying an army of Syracusans, he proceeded to chastise the Mamertines. City after city was taken from them, and after the signal defeat which they sustained at the River Longanus, peace was granted them through the friendly interference of the Carthaginians. Returning to Syracuse, the people saluted Hieron as king. Though Hieron had assisted the Romans with provisions in their siege of Rhegium, yet as the Romans opposed his attempt to drive the Mamertines out of Sicily, hostilities were begun between them. Hiero joined the Carthaginians, but getting little or no assistance, the Roman consuls effected a landing, and after some fighting a treaty was concluded. For upwards of forty years Hiero now remained the steady friend of the Romans. He gave them valuable aid during the first Punic War at the sieges of Agrigentum and Lilybæum. As a reward, the tribute which he formerly paid was remitted, and he was included in the treaty of peace at the close of the first Punic War, B.C. 241. After this he visited Rome, where he displayed great liberality, and received signal honours. At the breaking out of the second Punic War he remained equally steady in his friendship with the Romans, whom he assisted with ships and provisions. He is supposed to have died B.C. 216, upwards of ninety years of age.
His government was mild and eminently popular. He laid aside the pomp of royalty, and appeared undistinguishable from a private citizen. The corn laws which he established were so admirable, that in subsequent times when the Romans took possession of Sicily these laws were retained. His liberality extended to other nations besides the Romans. He sent assistance to the Rhodians, whose city had been destroyed by an earthquake, and in the largest ship then ever built he sent presents to Ptolemy king of Egypt.