Orontes III was King of Armenia

Armenia

Armenia , officially the Republic of Armenia , is a landlocked mountainous country in the Caucasus region of Eurasia...

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In his reign the royal capital was moved from Armavir

Armavir, Armenia

Armavir is a city located in western Armenia. The 1989 census reported that the city had a total population of 46,900, but this has declined considerably: the 2001 census counted 32,034; estimate for 2008 is 26,387. It is the capital of the Armavir province . The city of Armavir in Russia, founded...

 to Yervandashat

Yervandashat

Yervandashat is a village in the Armavir Province of Armenia. The village has a ruined basilica dated to the 4th or 5th century and the Saint Shushanik church of the 10th to 17th century...

 in 302 BC.
He struggled for control of the Kingdom of Sophene

Sophene

Sophene , or ) was a province of the Armenian Kingdom and of the Roman Empire, located in the south-west of the kingdom. It currently lies in modern-day southeastern Turkey....

 with king Antiochus II Theos

Antiochus II Theos

Antiochus II Theos was a king of the Hellenistic Seleucid Kingdom who reigned 261 BC – 246 BC). He succeeded his father Antiochus I Soter in the winter of 262–61 BC...

 until being defeated in 272 BC and was forced to pay a large tribute which included 300 talents of silver and 1,000 horses and mules.
Orontes III was subsequently murdered in 260 BC, whether at the instigation of King Antiochus II is nor recorded.
His son, Sames, continued to rule in Sophene

Sophene

Sophene , or ) was a province of the Armenian Kingdom and of the Roman Empire, located in the south-west of the kingdom. It currently lies in modern-day southeastern Turkey....

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