During his reign, he attempted to strengthen the Roman state and its religion, leading to the Decian persecution, where a number of prominent Christians (including Pope Fabian) were put to death.

Unlike some of his immediate imperial predecessors such as Philip the Arab or Maximinus Thrax who did not have extensive administrative experience before assuming the throne, Decius was a distinguished senator who had served as suffect consul in 232, had been governor of Moesia and Germania Inferior soon afterwards, served as governor of Hispania Tarraconensis between 235 and 238, and was urban prefect of Rome during the early reign of Emperor Philip the Arab.

[4] By the end of 248 or 249, Decius was sent to quell the revolt of Pacatian and his troops in Moesia and Pannonia; some modern historians see this rebellion as a reflection of emerging Balkan separatism.

Either as a concession to the Senate, or perhaps with the idea of improving public morality, Decius endeavoured to revive the separate office and authority of the censor.

[13] Anyone, including Christian followers, who refused to offer a sacrifice for the emperor and the Empire's well-being by a specified date risked torture and execution.

"[14] However, towards the end of the second year of Decius' reign, "the ferocity of the [anti-Christian] persecution had eased off, and the earlier tradition of tolerance had begun to reassert itself.

During his brief reign, Decius engaged in important operations against the Goths, who crossed the Danube to raid districts of Moesia and Thrace.

[15] In the meantime, Decius had returned with his re-organized army, accompanied by his son Herennius Etruscus and the general Trebonianus Gallus, intending to defeat the invaders and recover the booty.

The final engagement, the battle of Abritus, in which the Goths fought with the courage of despair, under the command of Cniva, took place during the second week of June 251 on swampy ground in the Ludogorie (region in northeastern Bulgaria which merges with Dobruja plateau and the Danube Plain to the north) near the small settlement of Abritus[2] or Forum Terebronii (modern Razgrad).

[12] As the historian Aurelius Victor relates: The Decii (i.e., Decius and his son), while pursuing the barbarians across the Danube, died through treachery at Abritus after reigning two years.

Very many report that the son had fallen in battle while pressing an attack too boldly; that the father however, has strenuously asserted that the loss of one soldier seemed to him too little to matter.

[20][21] The later telling of the Seven Sleepers, about seven Christian youths from Ephesus who fled the Decian persecution by hiding in a cave (walled up by Decius) and sleeping for almost 300 years, emerged.