User:HistoryofIran/List of shahanshahs of the Sassanid Empire

Phraates IV (Parthian: Frahāt, literally; the one with [regal] glory) was king of the Parthian Empire from 37 BC to 2 BC. He was appointed successor to the throne in 37 BC, after the death of his brother Pacorus I. He soon murdered his father and all his thirty brothers.

Background
Phraates was the son of Orodes II and the Commagene princess Laodice of Parthia. The original heir of Orodes II was his son Pacorus I, who was killed fighting Roman forces at the battle of Mount Gindarus. His death spurred a succession crisis in which Orodes II chose Phraates IV as his new heir.

Reign
Upon assuming the throne, Phraates IV eliminated rival claimants by killing and exiling his own brothers. One of them, Monaeses, fled to Antony and convinced him to invade Parthia. Antony defeated Parthia's Judaean ally Antigonus in 37 BC, installing Herod as a client king in his place.

The following year, when Antony marched to Erzurum, Artavasdes II of Armenia once again switched alliances by sending Antony additional troops. Antony invaded Media Atropatene (modern Iranian Azerbaijan), then ruled by Parthia's ally Artavasdes I of Media Atropatene, with the intention of seizing the capital Praaspa, the location of which is now unknown. However, Phraates IV ambushed Antony's rear detachment, destroying a giant battering ram meant for the siege of Praaspa; after this, Artavasdes abandoned Antony's forces.

The Parthians pursued and harassed Antony's army as it fled to Armenia. Eventually, the greatly weakened force reached Syria. After this, Antony lured Artavasdes II into a trap with the promise of a marriage alliance. He was taken captive in 34 BC, paraded in Antony's mock Roman triumph in Alexandria, Egypt, and eventually executed by Cleopatra VII of the Ptolemaic Kingdom.

Antony attempted to strike an alliance with Artavasdes I of Media Atropatene, whose relations with Phraates IV had recently soured. This was abandoned when Antony and his forces withdrew from Armenia in 33 BC; they escaped a Parthian invasion while Antony's rival Octavian attacked his forces to the west. Following Antony's suicide in Egypt followed by that of his wife Cleopatra in 30 BC, the Parthian ally Artaxias II reassumed the throne of Armenia.

Following the defeat of Antony and Cleopatra of Ptolemaic Egypt at the Battle of Actium in 31 BC, Octavian consolidated his political power and in 27 BC was named Augustus by the Roman Senate, becoming the first Roman emperor. Around this time, Tiridates II of Parthia briefly overthrew Phraates IV, who was able to quickly reestablish his rule with the aid of Scythian nomads. Tiridates fled to the Romans, taking one of Phraates' sons with him. In negotiations conducted in 20 BC, Phraates arranged for the release of his kidnapped son. In return, the Romans received the lost legionary standards taken at Carrhae in 53 BC, as well as any surviving prisoners of war. The Parthians viewed this exchange as a small price to pay to regain the prince. Augustus hailed the return of the standards as a political victory over Parthia; this propaganda was celebrated in the minting of new coins, the building of a new temple to house the standards, and even in fine art such as the breastplate scene on his statue Augustus of Prima Porta.

Along with the prince, Augustus also gave Phraates IV an Italian slave-girl, who later became Queen Musa of Parthia. To ensure that her child Phraataces would inherit the throne without incident, Musa convinced Phraates IV to give his other sons to Augustus as hostages. Again, Augustus used this as propaganda depicting the submission of Parthia to Rome, listing it as a great accomplishment in his Res Gestae Divi Augusti. When Phraataces took the throne as Phraates V (r. c. 2 BC – 4 AD), Musa married her own son and ruled alongside him. The Parthian nobility, disapproving of both the incestuous relationship and the notion of a king with non-Arsacid blood, forced the pair into exile in Roman territory.