PHRIAPATIUS (r. ca. 185-170 BCE), the third Arsacid king (see ARSACIDS), possibly first cousin once removed of Arsaces II (r. ca. 211-185 BCE), fraternal grandnephew of Arsaces I (r. ca. 248/7-211 BCE) and the father of the kings Phraates I (r. ca. 168-165/4 BCE), Mithridates I (r. ca. 165/4-132 BCE), and Artabanus I (q.v.; r. ca.127-126 BCE).

The traditional reign of Phriapatius (Parth. Friyapat, from Ir. *Friya-pati- ‘Herr des/der Lieben’, ‘Lieber Herr’, Schmitt, no. 386), who ruled under the name of Arsaces III, is circa 191-176 BCE, but it is increasingly likely that the beginning of his reign must be shifted to circa 185 BCE, with the death of Arsaces II (Karras-Klapproth, pp. 152-53; Assar, 2004; 2005; 2011, p. 116; Ellerbrock).  Phriapatius was probably the fraternal grandnephew of Arsaces I (though some argue that Phriapatius was his grandson) and the first cousin once removed of Arsaces II (while some argue that Phriapatius was his nephew) (Assar, 2005, pp. 35-36; 2011, p. 116; Overtoom, 2020, pp. 150-54, Olbrycht, pp. 220-22).

Once Phriapatius gained the throne, he reigned for fifteen years; however, little literary evidence of his long reign has survived (Justinus, Epit., 41.5.8-9). In replacing Arsaces II, Phriapatius certainly faced similar problems of trying to reconsolidate the authority of the Arsacids and the power of the Parthian state in the aftermath of Antiochus III’s anabasis (211-205 BCE; see ANTIOCHUS III Megas). Yet, the sudden military successes of Phriapatius’ successors likely would not have been possible without his efforts to rebuild the kingdom and rehabilitate the image of the king.

Phriapatius’ primary concern throughout his reign likely was the restoration of the Arsacids’ regional power in northeastern Iran. Arsaces I had placed great emphasis on expanding the Parthian military (see ARSACIDS viii. Military Architecture of Parthia), making the Parthian state a regional power (Justinus, Epit., 41.4.8; Overtoom, 2016; 2020, pp. 65-93; Olbrycht, pp. 162-79). Yet, Arsaces II’s unsuccessful campaign against Antiochus III severely damaged the Parthian military and diminished the size of the Parthian state (Polybius, 10.28-31; Overtoom, 2020, pp. 94-130).

With the sudden death of Antiochus III in 187 BCE, Arsaces II recognized an opportunity to reassert some of his former autonomy. The reoccupation of Hecatompylus and the renewal of independent Arsacid coinage (see ARSACIDS iii. Arsacid Coinage) in this period illustrate the growing momentum within Parthia to restore its full independence (Assar, 2004, pp. 80-82; Assar and Ghassem Bagloo; Rezakhani, p. 768). In fact, Phriapatius was the first Arsacid king to adopt the epithets “Great King” and “Divine King” on his late coinage (S10.1, S10.15, S10.18-19) (Assar, 2011, p. 116). Yet, although the Parthians were able to occupy a few neighboring cities abandoned by the Seleucids, no major military operations occurred under Arsaces II or Phriapatius.

While Arsaces II’s status as a subordinate ally of Antiochus III after 208 BCE helps explain the prolonged inactiveness of the Parthians during the remainder of most of his extensive reign, the long and uneventful reign of Phriapatius suggests that the Parthian state had remained relatively weak under Arsaces II. Thus, Phriapatius inherited a kingdom still suffering from economic and military hardships, and therefore, he did not openly challenge Seleucid hegemony by aggressively expanding his domain. Instead, the task of conducting major military operations fell to Phriapatius’ sons, Phraates I and Mithridates I.

Ultimately, Phriapatius’ great contributions to Parthian history were his determined domestic policy to restore the power and authority of the kingdom and his royal line. He likely had four sons, Phraates, Mithridates, Bagasis, and Artabanus, three of whom became future Arsacid kings (Assar, 2011, pp. 113-19; Overtoom, 2020, pp. 154-187, 239-49; Olbrycht, pp. 222-33). Phriapatius inherited a much-diminished kingdom, but his determined domestic policy to restore the power and authority of his domain and his royal line facilitated the rapid expansion of the Parthian state in the 160s-140s BCE (Overtoom, 2019; 2020, pp. 150-88).

New epigraphic evidence from Nisa (q.v.) possibly suggests that, when Phriapatius died in about 170 BCE, a previously unknown Arsacid king, now known as Arsaces IV, reigned briefly for two years before dying suddenly (Assar, 2005, p. 38; 2006, p. 88; 2006-2007; 2011, p. 116; Overtoom, 2020, pp. 151, 153, 159-60). His death in circa 168 BCE allowed the Parthian throne to pass to the eldest son of Phriapatius, Phraates I, who became Arsaces V. Phriapatius’ policy of strengthening the kingdom and army over a period of fifteen years appears finally to have produced results under the leadership of his eldest son, who became the first king to expand the boundaries of his kingdom outside of Parthia proper since Arsaces I.