When the Parths occupied the area as far as Caria, the Roman Emperor Antonius defeated the Parths via the help of his commanders also sent them away from Anatolia. following this incident, Antonius came to Anatolia and had various legal kingdoms established in order to form a tampon region between his own land also that of the Parths, so that he could prevent any Parth attacks. As a consequence of this, into B.C.39, the Mitridates Region inluding Amasya as fine was given to Dorius, the son of II. Pharnakes.
Amasya, in this term, was an crucial city which was the metropolis of the Mitridates Glaticus Region. In B.C. 25 ,the Emperor Augustus (B.C. 27- A.D.14) founded the Provincia Galatia and joined the Mitridates Region also several others to this province.
Throughout the reign of the Roman Empire , Amasya with a provincial status transformed into the centre of the road structure between provinces. intended instance, the roads of Galatia also Cappadocia used to have an conclusion in Amasya.
Head from the reign of Emperor Domitianus (A.D.81-96) up to that of Severus Alexandra (A.D.222-235) , the city coins were known to be minted into Amasya. Now, mainly of these coins are included into the coin collection of Amasya Museum.
The city of Amasya became the religious and administrative centre of Diospontus after Emperor Diocletianus and took location among Armenian castles which were Bizantyne’s military provinces from VIII. century onwards.