Nicomēdes in Harpers Dictionary of Classical Antiquities (1898)
Nicomēdes II., surnamed Epiphănes, king of Bithynia, reigned B.C. 149-91. He was the son and successor of Prusias II., and fourth in descent from the preceding. He was brought up at Rome, where he succeeded in gaining the favour of the Senate. Prusias, in consequence, became jealous of his son, and sent secret instructions for his assassination. The plot was revealed to Nicomedes, who thereupon returned to Asia, and declared open war against his father. Prusias was deserted by his subjects, and was put to death by order of his son, B.C. 149. Of the long and tranquil reign of Nicomedes, few events have been transmitted to us. He courted the friendship of the Romans, whom he assisted in the war against Aristonicus, 131. He subsequently obtained possession of Paphlagonia, and attempted to gain Cappadocia by marrying Laodicé, the widow of Ariarathes VI. He was, however, expelled from Cappadocia by Mithridates; and he was also compelled by the Romans to abandon Paphlagonia, when they deprived Mithridates of Cappadocia.
Nicomedes II of Bithynia in Wikipedia
Nicomedes II Epiphanes (Νικομήδης Β' ὁ Ἐπιφανής) was the king of Bithynia from 149 to c. 127 BC. He was fourth in descent from Nicomedes I. Nicomedes II was the son and successor of Prusias II and Apame IV. His parents were related, as they were first cousins.
He was so popular with the people that his father sent him to Rome to limit his influence. However in Rome, he also gained favor from the Roman Senate, forcing Prusias to send an emissary with secret orders to assassinate him. But the emissary revealed the plot, and persuaded the prince to rebel against his father.
Supported by Attalus II, king of Pergamum, he was completely successful, and ordered his father to be put to death at Nicomedia. During his long reign Nicomedes adhered steadily to the Roman alliance, and assisted them against Aristonicus of Pergamum. He was succeeded by his son.