Political map of Europe & the Mediterranean 15 January 54 AD (Iberian–Armenian War): Exploiting Parthian instability, Rhadamistus of Iberia (Kingdom of Iberia (antiquity)) invaded Armenia in 50 AD (War between Armenia and Iberia) and executed the king (Mithridates of Armenia), even though both were Roman allies. Although Rome accepted Rhadamistus’ power grab, Parthia—by now under the firm rule of Vologases I (51–78)—did not and in 52 AD marched into Armenia with their own claimant, Vologases’ brother Tiridates (Tiridates I of Armenia). However, the expedition was crippled by winter and disease, forcing Tiridates to withdraw the following year.