Marcus Aurelius Probus (August 19, 232 – October 6, 282) was a Roman general and one of several candidates for the position of Roman Emperor during the Great Roman Civil War.
Probus was born in Sirmium in Pannonia Inferior. He enlisted in the Roman army in 250. During the late 250s, he was made a military tribune by Emperor Valerian. Later, he distinguished himself as a general during the reign of Aurelian.
During the Gallic War for Independence, Probus was partially responsible for confronting the Gallic forces that invaded Italy. In particular, he was largely responsible for defeating the "sleeper army" commanded by Julius Saturninus. Aurelian began to fall out of favor with the people and the army of the Roman Empire as a result of the invasion of Italy, and Probus used this and his own recent victories as grounds for declaring himself Emperor. Probus began his candidacy for the throne on October 4, 275.
Just two days after Probus rebelled against Aurelian, Pinianus declared himself Emperor. Then on December 27, 275, Asclepiodotus deposed Aurelian and declared himself the rightful ruler. For several months, the three candidates tried to avoid fighting each other, as the Gallic Empire and several Germanic tribes were invading Pannonia and Noricum. In June 276, however, two clashes between Probus' forces and forces loyal to Asclepiodotus quickly escalated into a full-scale war.
Probus was recognized as Emperor in Sicily, southern Italy, Africa Proconsularis (until November 279), Epirus (October 279 – September 280), Cyrenaica and Crete, Egypt, and the Syrian provinces. His reign was characterized by efforts to achieve control over central and northern Italy. His provisional capital was Syracuse. The war effort was his first priority: the majority of the military forces that had been stationed in the African provinces were summoned to Italy, and domestic affairs were handled mainly at the provincial level.
Probus' reign came to an end in 280. In November of 279, Lucius Valerius Messalla, the governor of Africa Proconsularis, had declared himself Emperor; and during the summer of 280, he had managed to take over all of the areas controlled by Antiochianus, plus central Italy. Finally, the province of Epirus abandoned Probus on September 28, 280. After the loss of Epirus, several generals openly abandoned Probus, while others began planning a coup d'état to oust Probus. Probus tried to flee eastward, but he was arrested before he could leave Sicily. The generals who had been planning the coup took over Probus' regime on October 13, 280 and recognized Messalla as Emperor.
Messalla had Probus imprisoned for the remainder of the war. The war ended on May 30, 282. On October 4 of that year, Messalla held a show trial for Probus, in which Probus was blamed for starting the Great Roman Civil War and devastating Italy. Probus was executed two days later.