surnamed EUERGETES, was the son of Pharnaces I. and grandson of the preceding. (Just. 38.5; Clinton. F. H. vol. iii. p. 426.) The period of his accession is wholly uncertain; we only know that he was on the throne in B. C. 154, when he is mentioned as sending an auxiliary force to the assistance of Attalus II. against Prusias, king of Bithynia. (Plb. 33.10.) But as much as twenty-five years before (B. C. 179), his name is associated with that of his father in the treaty concluded by Pharnaces with Eumenes, in a manner that would lead one to suppose he was already admitted to some share in the sovereign power. (Plb. 26.6.) He was the first of the kings of Pontus who entered into a regular alliance with the Romans, whom he supported with some ships and a small auxiliary force during the third Punic war. (Appian, App. Mith. 10.) At a subsequent period he rendered them more efficient assistance in the war against Aristonicus (B. C. 131-129), and for his services on this occasion was rewarded by the consul M'. Aquillius with the province of Phrygia. The acts of Aquillius were rescinded by the senate on the ground of bribery, but it appears that Mithridates continued in possession of Phrygia till his death. (Just. 37.1, 38.5; Appian, App. Mith. 12, 56, 57 ; Oros. 5.10; Eutrop. 4.20, who, however, confounds him with his son.) The close of his reign carl only be determined approximately, from the statements concerning the accession of his son, which assign it to the year 120. He was assassinated at Sinope by a conspiracy among his own immediate attendants. (Strab. x. p.477.)
A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890