Short answers, pulled from the story.
The year 321 BC marks the moment when Orontes III and Mithridates of Lesser Armenia declared their independence, transforming a satrapy into two distinct kingdoms. This shift occurred after Alexander the Great's Macedonian Empire defeated Persia at Gaugamela in 331 BC.
Tigranes the Great entered Syria following an invitation from factions embroiled in civil wars in 83 BC and established Tigranakert as the new capital with a population of 120,000 citizens living among temples and an amphitheater. His empire incorporated Iberia, Albania, Cappadocia, Cilicia, Judea, and parts of Parthia before Rome defeated Armenia in 69 BC ending its brief status as a regional empire.
Tiridates I received his crown from Emperor Nero in AD 66 during a ceremony that symbolized Roman-Parthian compromise. The Treaty of Rhandeia in 63 established that members of the Parthian Arsacid dynasty would rule Armenia as client kings of Rome.
The date traditionally marks 301 as when Armenia became the first state to adopt Christianity officially after Tiridates III accepted Christianity following being converted by Gregory the Illuminator. Apostles Bartholomew and Thaddeus spread faith through the region during the first century AD before kings Sanatruk, Axidares, Khosrov I, and Tiridates III persecuted Christians.
Tigranakert served as imperial capital with 120,000 residents living among many temples. Strabo recorded that Hannibal advised the building of Artashata near the junction of trade routes connecting Greece, Bactria, India, and the Black Sea while the army included 12,000 cavalrymen and 120,000 infantrymen according to ancient accounts.