The Gallic emperor besieges and captures Moguntiacum,…

The Goths are now retreating by land from their plunder of Greece’s Aegean coastal cities into the province of Pannonia, their invasion leading to disaster and even threatening Rome, while the Alamanni, a loosely knit confederation of tribes composed of fragments of several Germanic peoples, are simultaneously raising havoc in the northern part of Italy.

Emperor Gallienus, now fifty, halts the progress of the Alamanni by defeating them in battle in April 268, then turns north and wins several victories over the Goths.

His attention demanded by problems in Italy, Gallienus returns there without further pursuit of the survivors, who flee to armed encampments to the northeast.

In the autumn, he turns on the Goths once again, leading a large Roman force into Moesia to cut off the Gothic army.

Claudius, having succeeded Gallienus as emperor leads the Roman army to victory (although the cavalry commander Lucius Domitius Aurelianus is the real victor) at the Battle of Naissus, where the Romans slaughter the Goths by the thousands in 269.

Large numbers on both sides are killed but, at the critical point, the Romans trick the Goths into an ambush by pretended flight.

Some fifty thousand Goths are allegedly killed or taken captive.

It seems that Aurelian, who was in charge of all Roman cavalry during reign of Claudius, led the decisive attack in the battle.

A large number of Goths manages to escape towards Macedonia, initially defending themselves behind their laager.

Soon, many of them and their pack animals, distressed as they are by the harassment of the Roman cavalry and the lack of provisions, die of hunger.

The Roman army methodically pursues and surrounds the survivors at Mount Haemus where an epidemic affects the entrapped Goths.

After a bloody but inconclusive battle, they escape but are pursued again until they surrender.

Prisoners are admitted to the army or given land to cultivate and become coloni.

The members of the pirate fleet, after the failed attacks on Crete and Rhodes, retreat and many of them suffer a similar end.

However, the plague also affects the pursuing Romans and emperor Claudius, who will die from it in 270.

Paul of Samosata, bishop of Antioch from about 260, argues that Jesus was God strictly in the sense that an influence or power from God the Father rested upon Jesus, God's human person.

Paul's advancement of this doctrine of dynamic Monarchianism earns him condemnation at various synods held in Antioch, not only for his teachings, which anticipate adoptionism, but also for his financial interests and personal conduct.

He is deposed from his bishopric in 269 by seventy bishops, priests, and deacons assembled at Antioch, who elect one Donus as his successor.

Despite being deposed by this synod, Paul still considers himself bishop and since he has friendly relations to Zenobia, the separatist queen of Palmyra ruling in Syria, he continues to occupy the bishop's house in Antioch.

Zenobia, not content to remain a Roman client, crosses the line into open rebellion when she proclaims her independence from Rome in 269, while Claudius Gothicus, the successor of Emperor Gallienus, is preoccupied with defending the borders of the empire against Germanic invasions.

Atyling herself queen regent of Palmyra, she has her own young son Wahballat adopt his father's titles of “king of kings” and “corrector totius Orientis”.

Roman officials in the East are caught between loyalty to the emperor and Zenobia's increasing demands for allegiance. 

Claudius, turning his attention to the shaky Gallic empire, sends into southern Gaul an army detachment under Iulius Placidianus, Praefectus Vigilium (i.e.

Prefect of the Roman Watch), which meets no significant resistance in restoring to Rome the territory east of the river Rhône.

Placidianus next opens talks with the Iberian provinces, which return to the Roman fold.

Claudius, having stayed the winter in Rome, renews persecution of Christians in 269. (One such, a Roman priest believed to have been martyred during this persecution and buried on the Flaminian Way, is one of the models for Saint Valentine; another is probably a bishop of Terni who was martyred in Rome.)

Claudius is unable to deal with the ascendant Palmyrene kingdom, as he is still occupied with driving the Goths out of the Balkans.

News arrives of an invasion by the Juthungi (Marcomanni, or possibly Jutes) in Raetia, the province comprising Vorarlberg and Tirol states in present-day Austria, the eastern cantons of Switzerland, and parts of Bavaria and Baden-Württemberg states in Germany.

Reports also warn of an imminent attack on Pannonia by the Vandals, a Germanic people.

Determined to counter this, he makes for Sirmium in order to prepare for action after assigning command of the Gothic campaign to Aurelian, fifty-five, a Danubian-born man of modest origins who had risen through the cavalry ranks to be appointed by Claudius commander in chief of the army on the Lower Danube.

Claudius, having earned the title Gothicus by repelling the Goths' invasion of the Balkans in 269, meanwhile campaigns successfully against the Goths in the east.

Allied to the Goths are the Gepids, a Germanic tribe that had lived on the southern Baltic coast in the first century CE, having migrated there from southern Sweden some years earlier, and again migrated southward during the second century.

The emperor gives captives the choice of settlement in the Danubian provinces or service in the Roman army.

The victories of Gallienus on the Nestus and Claudius at Naissus (Nish) had reduced the danger to the Roman empire, but the countries of the middle Danube are still under pressure by the Marcomanni, the Quadi, the Iazyges, the Sarmatians, and the Carpi of free Dacia, who will soon joined by the Roxolani and the Vandals.

In spite of stubborn resistance, Dacia is gradually being overwhelmed, and it now begins to be abandoned by the Roman troops, though not evacuated officially.

Emperor Claudius dies in January 270 of the plague, which has already caused great losses among the Goths; he has reigned for only eighteen months.

Wwhile preparing a campaign against the Vandals, he had fallen ill on the march to the battle and returned to his regional headquarters in Sirmium, leaving Aurelian in charge of operations against the Goths.