in Asia Minor. However, the one was defeated in attempting to invade
Europe and the other was overthrown by Odaenathus. In recognition of his
services Gallienus bestowed upon him the title of "Commander of the East"
(_dux orientis_), with the duty of protecting the East (264 A. D.). In
Palmyra, he ruled as _basileus_, or king, and although he nominally
acknowledged the overlordship of the Roman emperor, he was practically an
independent sovereign.

*The Goths.* A fresh peril arose in the maritime raids of the Goths,
Heruli, and other tribes who had seized the harbors on the north coast of
the Black Sea. With the ships that they thus secured they ravaged the
northern coast of Asia Minor as early as 256 A. D. In 262 they forced the
passage of the Bosphorus and Hellespont and plundered the shores of the
Aegean. Their most noted raid was in 267, when they sacked the chief
cities of Greece, including Athens.

No less than eighteen usurpers, for the most part officers who had risen
from the ranks, had unsuccessfully challenged the authority of Gallienus
in the various provinces. At last, in 268 A. D., one of his leading
generals, Aureolus, laid claim to the imperial title. Gallienus defeated
him and was besieging him in Milan, when he was killed at the instigation
of his officers, who proclaimed as his successor one of their own number,
Marcus Aurelius Claudius.

*Claudius Gothicus, 268-270 A. D.* The rule of Claudius lasted only two
years, in which his greatest achievement was the crushing defeat which he
inflicted upon the Goths who had again overrun Greece and the adjacent
lands (269 A. D.). This victory won him the name of Gothicus. Upon the
death of Claudius in 270 A. D., the army chose Lucius Domitius Aurelianus
as emperor.

*Lucius Domitius Aurelianus, 270-275 A. D.* Aurelian's first task was to
clear Italy and the Danubian provinces of barbarian invaders. Two
incursions of the Alamanni into Raetia and Italy were repulsed, the latter
with great slaughter. But the emperor recognized that the security of
Italy could no longer be guaranteed and so he ordered the fortification of
the Italian cities. The imposing wall which still marks the boundary of
part of ancient Rome was begun by Aurelian. A horde of Vandals were beaten
and driven out of Pannonia and a victory was won over the Goths in Moesia.
But the exposed position of Dacia, and the fact that it was already in
large part occupied by the barbarians, induced Aure