There were 26 emperors in a 49-year period, a signal of political instability. Maximinus Thrax was the first ruler of that time, governing for just three years. Others ruled just for a few months, like Gordian I, Gordian II, Balbinus and Hostilian. The population and the frontiers were abandoned, since the emperors were mostly concerned with defeating rivals and establishing their power. The economy also suffered during that epoch. The massive military expenditures from the Severi caused a devaluation of Roman coins. Hyperinflation came at this time as well. The Plague of Cyprian broke out in 250 and killed a huge portion of the population. In 260 AD, the provinces of Syria Palaestina, Asia Minor and Egypt separated from the rest of the Roman state to form the Palmyrene Empire, ruled by Queen Zenobia and centered on Palmyra. In that same year the Gallic Empire was created by Postumus, retaining Britannia and Gaul. These countries separated from Rome after the capture of emperor Valerian by the Sassanids of Persia, the first Roman ruler to be captured by his enemies; it was a humiliating fact for the Romans. The crisis began to recede during the reigns of Claudius Gothicus (268–270), who defeated the Gothic invaders, and Aurelian (271–275), who reconquered both the Gallic and Palmyrene Empires. The crisis was overcome during the reign of Diocletian.