the Roman forces pulled out of Mesopotamia in the winter of 65/4 BC, and Pompey resumed his war against Mithridates VI, Phraates III took advantage of the situation and invaded Armenia at the start of 64 BC. Phraates III ultimately reached an accord with Pompey and Tigranes; Mesopotamia and Adiabene were confirmed as Parthian territory, while Gordyene was confirmed as Armenian. Furthermore, a peace treaty was established between Phraates III and Tigranes. Coinage and Imperial ideology Phraates III was the penultimate Parthian king to use the legend of "King, God" in his coinage (the first Parthian to use it being Mithridates I), an uncommon title amongst the Parthian monarchs. The last Parthian ruler to use the title was Mithridates IV. Other titles used by Phraates III were Epiphanes, Theopator and Eupator. According to the modern historian Edward Dąbrowa, these titles were seemingly used by the Parthians as a method to back their claims to the throne, "through their close relation to the divine ancestor, or by their own divine status." Phraates III also used the titles of King of Kings and Great King. Like the rest of the Parthian kings, he used the title of Arsaces—the name of the first Parthian ruler Arsaces I ()—on his coinage. This had become a royal honorific among the Parthian monarchs out of their admiration for his achievements. On the obverse of his coins, Phraates III used two types of headgear; a tiara decorated with a line of stags, and a unique diadem inspired by the Hellenistic diadem. After his death, the tiara does not appear on Parthian coinage for some time. The coinage of Phraates III influenced the Parthian vassal kingdom of Persis; its king, Pakor I, adopted the same hairstyle used on the observe of Phraates III's coins. On the reverse of Phraates III's tetradrachms, an altered version of the traditional seated archer-figure is depicted; instead of a sleeved coat, he is now wearing the same open-necked tunic worn by Phraates III on the observe of his coins. According to the modern historian Vesta Sarkhosh Curtis, "The archer on the reverse is now clearly the same person as the king on the obverse." A bird similar to the eagle of the Greek god Zeus has also been added on the hand of the seated figure. In the Parthian era, Iranians used Hellenistic iconography to portray their divine figures, thus the eagle can