Phraates IV Silver Drachm Series: Typology, Epigraphy, and Iconography

Historical Context

Phraates IV (Parthian: Frahāt, reigned c. 38/37–2 BC) assumed the Arsacid throne following a profound political and military crisis. In 38 BC, crown prince Pakoros I was killed in battle against Roman forces led by Publius Ventidius Bassus at Mount Gindarus. The aging king Orodes II appointed Phraates IV as his successor. Upon taking power, Phraates murdered his father and executed approximately thirty half-brothers alongside their families to preempt rival claims to the Arsacid diadem.

This domestic purge caused prominent members of the nobility to seek protection abroad. The grandee Monaeses defected to Mark Antony, providing Rome with an incentive to intervene directly in Parthian affairs. In 36 BC, Antony launched a major campaign with sixteen legions, advancing through Armenia into Media Atropatene to besiege the fortress of Phraaspa. Phraates IV deployed his cavalry against the Roman supply lines, ambushing and destroying the siege train commanded by Oppius Statianus and decimating two escort legions. Deprived of siege equipment and harassed by mounted archers, Antony was forced into a punishing autumn retreat through the Armenian mountains, sustaining severe losses.

Despite this military triumph, Phraates soon faced internal insurrection. Around 32–29 BC, the Parthian aristocracy revolted and elevated Tiridates II to the throne. Phraates fled northeast to secure support from nomadic allies (Scythians, Dahae, or Saka) and successfully reestablished his authority, compelling Tiridates to escape to Roman Syria with one of Phraates' sons as a hostage.

These events established the geopolitical backdrop for the diplomatic accord of 20 BC between Phraates IV and the Roman emperor Augustus. In exchange for the repatriation of his son, Phraates returned the Roman legionary eagles and surviving prisoners captured at Carrhae in 53 BC and during Antony's failed invasion. As part of this diplomatic exchange, Augustus presented Phraates with an Italian consort named Musa. She rose to the status of principal queen, bore him a son named Phraataces (Phraates V), and convinced the king around 10/9 BC to send his elder legitimate sons to Rome as guests and hostages. In 2 BC, Musa and Phraataces poisoned Phraates IV, concluding a thirty-six-year reign.

Obverse Iconographic Composition

The obverse dies of the drachm series present the left-facing portrait of Phraates IV executed in the developed Arsacid imperial style:

• Headdress and Coiffure: The king wears a royal diadem tied with multiple bands that hang behind the neck. His hair is dressed in several horizontal rows of formal, wavy curls that cover the ears. The beard is neatly squared or pointed, paired with a carefully engraved mustache.
• Torque and Robes: Around the monarch's neck is a spiraled, segmented torque, frequently terminating in ornamental ends such as animal terminals or pellets. He wears a heavy V-neck tunic fastened at the breast.
• The Royal Wart (Verruca): Dies consistently feature a prominent raised globule or wart on the temple or forehead. Far from an engraver's flaw, this anatomical marker is found across several mints and reappearances in later reigns, serving as a physical badge of genuine Arsacid lineage.
• Subsidiary Field Devices: The silver drachm coinage is divided into four major stylistic and chronological groupings based on the presence and arrangement of secondary symbols around the portrait:
  1. Plain field without secondary emblems.
  2. Crowning eagle positioned behind the royal bust, clutching a wreath in its beak.
  3. Crowning eagle behind the bust, paired with an eight-pointed star in the upper left field.
  4. Crowning eagle behind the bust, paired with an eight-pointed star situated above a crescent moon in the upper left field.
• Border: A regular pelleted border typically encloses the entire obverse design.

Obverse Epigraphy and Inscriptions

The obverse dies of Phraates IV's silver drachms are entirely anepigraphic. No royal names, titles, dates, or administrative signatures appear on the obverse face of the coin; all epigraphic and monographic data are reserved strictly for the reverse dies.

Reverse Iconographic Composition

The reverse features the traditional national emblem of the Arsacid dynasty:

• The Seated Archer: Arsaces I, the progenitor of the dynasty, is depicted seated facing right upon a high-backed or low-backed throne. He is clad in the customary nomadic equestrian dress of northern Iran, consisting of a soft fabric hood (bashlyk) tied beneath the chin, a long-sleeved belted tunic, and loose trousers tucked into boots.
• The Bow: With his right arm extended forward, Arsaces holds an asymmetrical composite recurve bow. His left arm rests near his lap or against the throne structure.
• Mint Monogram: Engraved directly beneath the extended bow is a ligature or monogram designating the issuing administrative workshop, most commonly the complex monogram associated with Ekbatana.
• Framing: Unlike contemporary Hellenistic coinages, the reverse design usually dispenses with an outer circular border of dots or bead-and-reel, ending cleanly with the external boundary of the rectangular inscription.

Reverse Epigraphy and Inscriptions

The reverse inscription surrounds the enthroned archer on four sides, arranged in a formal rectangular framework of seven parallel Greek lines:

• Line 1 (top, horizontal): ΒΑΣΙΛΕΩΣ
• Line 2 (right field, reading downward): ΒΑΣΙΛΕΩΝ
• Line 3 (exergue/bottom, upper line): ΑΡΣΑΚΟΥ
• Line 4 (exergue/bottom, lower line): ΕΥΕΡΓΕΤΟΥ
• Line 5 (left field, inner line reading upward): ΔΙΚΑΙΟΥ
• Line 6 (left field, middle line reading upward): ΕΠΙΦΑΝΟΥΣ
• Line 7 (left field, outer line reading upward): ΦΙΛΕΛΛΗΝΟΣ

Transliteration and Translation

• Transliteration: Basileōs Basileōn Arsakou Euergetou Dikaiou Epiphanous Philellēnos
• Translation: "Of the King of Kings Arsaces, Benefactor, Just, Manifest [God], Friend of the Greeks"

Epigraphic Style and Letterforms

The characters are cut in the formal square Greek chancery script characteristic of late-1st-century BC Arsacid administration. Notable letterforms include the square omicron (rendered as an open or closed square block), the square theta, and lunate or block sigmas. On various plateau issues, local engravers unfamiliar with Hellenistic Greek cut these texts mechanically, resulting in blundered letters, split strokes, or semi-abstract geometric substitutions.

Typology and Documented Variants

The silver drachm production of Phraates IV is struck on a reduced Attic weight standard, with recorded weights generally falling between 3.50 g and 4.20 g, flan modules measuring between 18 mm and 21 mm, and a regular 12-hour die axis. For comparative purposes, an authentic reference specimen in the British Museum (accession 1894,0506.2124) weighs 3.73 g at a diameter of 19 mm with a 12h alignment.

Drachm issues are classified into four principal typological categories based on obverse secondary attributes. Note that Sellwood Type 50 represents dated tetradrachms struck at Seleucia on the Tigris and contains no silver drachms; similarly, Sellwood 51.1–51.43 comprise tetradrachms, with drachm strikings beginning at subtype 51.44.

Major Typological Groups

Scholarly Debates and Attribution Limitations

1. Ideological Nature of the Crowning Eagle

The introduction of the eagle holding a wreath in its beak behind the royal head on Types 52 through 54 has generated two prominent scholarly interpretations:

• Hellenistic Victory Paradigm: Many numismatists interpret the bird as an imperial victory emblem adapted from Greek iconography (substituting for Nike) or Roman military standards, specifically commemorating the defeat of Mark Antony's legions at Phraaspa in 36 BC.
• Zoroastrian Royal Charisma (Khvarnah): Iranian specialists propose that the eagle represents the avian avatar of Verethragna, the Zoroastrian divinity of victory and triumph. In this framework, the bird bestows the divine kingly aura (farr or khvarnah), reinforcing the monarch's divine right to rule among his eastern Iranian subjects.

2. The Dynastic Significance of the Forehead Globule

Historically, the raised nodule on the forehead of Phraates IV was occasionally dismissed as a benign tumor (verruca vulgaris) or an accidental flaw in die preparation. Contemporary research favors an intentional dynastic marker. Because identical facial markings appear deliberately rendered on coins of earlier rulers and subsequent Arsacid claimants (such as Vardanes II and Meherdates), the feature is widely understood as a hereditary physical trait demonstrating legitimate descent from Arsaces I.

3. Mint Monogram Identification

While the ligature attributed to the imperial capital at Ekbatana (modern Hamadan) is securely identified through vast hoard patterns and continuous production, several secondary monograms remain conventional working hypotheses. Marks traditionally linked to regional centers such as Traxiane, Margiana, or Laodicea in Media await decisive confirmation through comprehensive die-link studies. A number of researchers suggest that certain monograms may designate military paymasters or mobile administrative workshops accompanying the king rather than stationary civic mints.

References

1. Parthia.com: Attribution Correlation Chart (Sellwood / Shore / BMC). Correlation tables for Phraates IV (Sellwood Types 51–54; Shore 274–304)
2. Parthia.com: Sellwood Database Records for Phraates IV. Subtype records for Sellwood 51.44–51.52, 52.10–52.39, 53.1–53.22, 54.7–54.16
3. British Museum Collection Online: Specimen 1894,0506.2124. AR Drachm of Phraates IV (Sellwood 54.7, BMC 219), 3.73 g, 19 mm, 12h
4. Numista: Roman Provincial Coin ANS 1944.100.58410 Reference. Corrected concordance identifying accession ANS 1944.100.58410 as Hadrian Æ35 of Alexandria
5. Justin, Epitome of the Philippic History of Pompeius Trogus. Book 42.5 (Accession, purges, wars with Mark Antony and Tiridates II)
6. Augustus, Res Gestae Divi Augusti. Chapters 29 and 32 (Return of standards and diplomatic settlement)
7. Strabo, Geography. Book 16.1.28 (Parthian royal hostages sent to Rome)