and easily
captured the two great cities of Babylon and Seleucia, which on his
approach were evacuated by their garrisons. He then proceeded to the
attack of Ctesiphon itself, passing his ships probably through one of
the canals which united the Tigris with the Euphrates, or else (like
Trajan) conveying them on rollers across the neck of land which
separates the two rivers.

Volagases had taken up his own position at Ctesiphon, bent on defending
his capital. It is possible that the approach of Severus by the line of
march which he pursued was unexpected, and that the sudden presence of
the Romans before the walls of Ctesiphon came upon the Parthian
monarch as a surprise. He seems, at any rate, to have made but a poor
resistance. It may be gathered, indeed, from one author that he met the
invaders in the open field, and fought a battle in defence of Ctesiphon
before allowing himself to be shut up within its walls. But after the
city was once invested it appears to have been quickly taken. We hear of
no such resistance as that which was soon afterwards offered by Hatra.
The soldiers of Severus succeeded in storming Ctesiphon on the first
assault; the Parthian monarch betook himself to flight, accompanied by
a few horsemen; and the seat of empire thus fell easily--a second
time within the space of eighty-two years--into the hands of a foreign
invader. The treatment of the city was such as we might expect from
the ordinary character of Roman warfare. A general massacre of the
male population was made. The soldiers wore allowed to plunder both the
public and the private buildings at their pleasure. The precious metals
accumulated in the royal treasury were seized, and the chief ornaments
of the palace were taken and carried off. Nor did blood and plunder
content the victors. After slaughtering the adult males they made
prize of the women and children, who were torn from their homes without
compunction and led into captivity, to the number of a hundred thousand.

Notwithstanding the precautions which he had taken, Severus appears
to have become straitened for supplies about the time that he captured
Ctesiphon. His soldiers were compelled for some days to exist on roots,
which produced a dangerous dysentery. He found himself unable to pursue
Volagases, and recognized the necessity of retreating before disaster
overtook him. He could not, however, return by the route of the
Euphrates, since his army had upon its advance compl