Europe 242: Gordian III’s Persian War
Pupienus and Balbinus ruled Rome for just a few months before they were assassinated by the Praetorian Guard in July 238, leaving the 13-year-old Gordian III as sole emperor. Meanwhile, Sasanian Persia continued to expand, capturing Hatra, capital of the Roman-aligned Kingdom of Araba, in 240 or 241. From Hatra, the Persians invaded the Roman Empire itself, leading Gordian to rally his troops and declare war in 242.
238 Disbandment of Legio III Augusta▲
In 238, following the victory over Maximinus Thrax, Gordian III ordered the disbandment of the Legio III Augusta due to its role in the deaths of his grandfather and uncle, Gordians I and II. The legionaries were either sent to the Rhine or dispersed among the African provinces. This left Africa without a legion, leading to the abandonment of the system of interior fortifications set up during the reign of Septimius Severus.
238–239? Sack of Histria▲
In 238, during the reign of Pupienus and Balbinus, the Carpi and Goths crossed the Danube into Lower Moesia. There they sacked the city of Histria, but were eventually bribed to leave by governor Tullius Menophilus. Another incursion in 242—probably Goths—was defeated by Gordian III near the city of Dionysupolis during his march to the Persian front.
29 Jul 238 End of Pupienus and Balbinus▲
From the start, the Praetorian Guard resented that Pupienus and Balbinus had received the imperial office from the Senate and plotted against them. At the end of the Capitoline Games, the Praetorians rushed into the palace, catching Pupienus and Balbinus still arguing over whether to call on the former’s loyal German auxiliaries. The two co-emperors were dragged through the streets into the Praetorian Camp, where they were finally executed and Gordian III was proclaimed sole emperor.
29 Jul 238–11 Feb 244 Principate of Gordian III▲
The deaths of Pupienus and Balbinus in July 238 left the 13-year-old Gordian III as the sole Roman emperor. Due to his age, the imperial government was surrendered to the aristocratic families, who controlled Roman affairs through the Senate. In 241 Gordian married Furia Sabinia Tranquillina, daughter of the newly-appointed Praetorian prefect Timesitheus, securing Timesitheus’ position as the most power person in the Empire. Gordian’s reign came to an abrupt end in 244, when both he and his father-in-law died near the Persian front in unclear circumstances.
In 240 Sabinianus—probably the governor of Africa Proconsularis—revolted against Gordian III, proclaiming himself Emperor and attempting to rally the other African provinces behind him. However, the governor of Mauretania Caesariensis remained loyal to Gordian and, after dealing with local conspirators, marched into Carthage. Defeated, the rebels surrendered Sabinianus to the authorities in return for amnesty.
241? Fall of Hatra▲
In the late 230s Shah Ardashir I of Persia consolidated nearly 50,000 troops around Hatra, capital of the Kingdom of Araba, and constructed massive siege works consisting of more than 12 km of circumvallation and contravallation walls (longer than those used by the Romans at Jerusalem and Masada in 70 and 73 AD combined). After a two- or four-year siege—during which it received almost no help from its Roman allies—Hatra finally capitulated to Ardashir and his heir Shapur some time between 12 April 240 and 1 April 241. Following this, Araba was absorbed into the Persian Empire and Hatra abandoned.
241?–242 Ardashir I’s capture of Nisibis▲
Some time between 235 and 241—but probably after the fall of Hatra (240/241)—Shah Ardashir I of Persia took advantage of Roman instability following Maximinus Thrax’s seizure of power to make a renewed invasion of Roman Mesopotamia. This time Ardashir and his son and heir, Shapur I, successfully captured Nisibis, after a siege of under a year. The Persians then advanced into the neighboring province of Osrhoene, seizing the important cities of Carrhae and Edessa, before advancing to the outskirts of Antioch by 242.