Laodice was the daughter born from the sibling union of the Seleucid rulers Antiochus IV Epiphanes and Laodice IV.... In 152 BC, Laodice became one of the supporters for her brother Alexander Balas, who revolted and overthrew the Seleucid king Demetrius I Soter, who was their maternal half-brother/cousin.
After 152 BC, Laodice married King Mithridates V of Pontus, who reigned from 150–120 BC. Mithridates V and Laodice VI were related, as her husband had lineage from the Seleucid dynasty. Little is known regarding her relationship with her husband or her reign as Pontian queen. During their marriage, Laodice bore Mithridates V seven children: Laodice of Cappadocia, Mithridates VI of Pontus, Mithridates Chrestus, Laodice, Nysa (sometimes spelt as Nyssa), Roxana and Statira. Nysa, Roxana and Statira were put to death after the fall of the Kingdom of Pontus in 63 BC.
Mithridates V was assassinated in about 120 BC in Sinope poisoned by unknown persons at a lavish banquet which he held. In the will of Mithridates V, he left the kingdom to the joint rule of Laodice, Mithridates VI and Mithridates Chrestus. Both of her sons were underage to rule and Laodice retained all power as regent.
Laodice in her regency favored her second son over her first son. During her regency 120–116 BC (even perhaps up to 113 BC), Mithridates VI escaped from the plotting of his mother and had gone into hiding. She enjoyed luxuries that made her a compliant client of Rome. She accepted bribes from the Roman Republic and her extravagance pushed Pontus into debt.
Mithridates VI between 116–113 BC returned to Pontus from hiding and was hailed king. He was able to remove his mother and his brother from the Pontian throne, thus Mithridates VI became the sole ruler of Pontus. Mithridates VI show clemency towards his mother and brother, by imprisoning them both. Laodice VI died in prison of natural causes, however his brother Mithridates Chrestus could have died in prison from natural causes or was tried for treason and was executed on the orders of his brother. When they died, Mithridates VI gave his mother and brother a royal funeral. 1
Mithridates V Euergetes was assassinated probably in 120 when his son Eupator was about thirteen years old. It is not clear what testimentary arrangements Euergetes made, whether he specified a joint rule of his widow and eldest son Eupator (Memnon 22.2), with perhaps their second son too (Strabo 10.4.10 c.477), or just a regency for his wife until Eupator should be old enough to govern for himself. At any rate Euergetes' queen took over the power, and according to Justin (Epit. 37.2), to secure her own position she tried to do away with Eupator: the boy's guardians, we are told, forced him to ride and throw the javelin from a dangerous horse, and when this failed to kill him, they turned to the surer means of poison. He was on his guard, however, and took antidotes to build up an immunity, which worked so effectively that he was unable to kill himself by poison at the end of his reign (App. Mith. 111). 2