The article is devoted to the reign of Constantius Gallus, who was Caesar (junior emperor) in the East of the Roman Empire in 351-354 AD. The purpose of the article is to study the peculiarities of his rule in the context of the political system of the Roman Empire in the middle of the IV century AD. Among the tasks of the article are the following: disclosing the features of the description of the reign of Gallus in the sources, determining the scope of powers delegated to him by Augustus Constantius II; analysis of the main vectors of policy of Caesar Gallus as emperor; clarifying the circumstances of Caesar Gallus conflict with Constantius II and his assassination. The main source for the reign of Gallus is Ammianus Marcellinus, who portrayed the emperor in a negative way as a cruel and despotic man. But the true figure of Caesar, his reigns were more multifaceted. The main problems of the reign of Gallus were laid down during his appointment by Constantius II. The senior emperor endowed his junior colleague with very narrow powers, which concerned primarily the military sphere. At the same time, Caesar was effectively deprived of powers in the administrative, financial, and legal spheres. Local provincial officials did not perceive him as their immediate superior and focused on Constantius II. At the same time, the population saw in him a full-fledged ruler and turned to him to solve their problems. To meet the demands of the population, Gallus had to go beyond the limits set by the senior emperor, which made a conflict between the two rulers inevitable. The rule of Gallus itself combined successes and failures. He managed to stop the military aggression of the Persians on the borders, to suppress the actions of Isaurians and Jews within the state, to promote the development of Christianity. At the same time, he failed to resolve the food crisis in the territories under his control, entered into a fierce confrontation with the curia of Antioch, and showed excessive cruelty and rage in the government. Constantius II saw Gallus departure for the powers granted to him as an attempt to usurp power. Eventually, Augustus began to perceive Caesar as a threat to himself and went to the physical destruction of Gallus in order to eliminate this threat.
Source: Pukhovets D. (2021). The Reign of Caesar Gallus: the Reasons for Failure. Antiquities of Lukomorie. №4: 7-21