w, which had been just enacted, that all
conversions to Christianity should be free and voluntary. See Baronius,
Annal. Eccles. A.D. 409, No. 12, A.D. 410, No. 47, 48.]

[Footnote 86: Zosimus, l. v. p. 367, 368, 369. This custom of swearing
by the head, or life, or safety, or genius, of the sovereign, was of the
highest antiquity, both in Egypt (Genesis, xlii. 15) and Scythia. It was
soon transferred, by flattery, to the Caesars; and Tertullian complains,
that it was the only oath which the Romans of his time affected to
reverence. See an elegant Dissertation of the Abbe Mossieu on the Oaths
of the Ancients, in the Mem de l'Academie des Inscriptions, tom. i. p.
208, 209.]

While the emperor and his court enjoyed, with sullen pride, the security
of the marches and fortifications of Ravenna, they abandoned Rome,
almost without defence, to the resentment of Alaric. Yet such was the
moderation which he still preserved, or affected, that, as he moved with
his army along the Flaminian way, he successively despatched the
bishops of the towns of Italy to reiterate his offers of peace, and
to congradulate the emperor, that he would save the city and its
inhabitants from hostile fire, and the sword of the Barbarians. [87]
These impending calamities were, however, averted, not indeed by the
wisdom of Honorius, but by the prudence or humanity of the Gothic king;
who employed a milder, though not less effectual, method of conquest.
Instead of assaulting the capital, he successfully directed his efforts
against the Port of Ostia, one of the boldest and most stupendous
works of Roman magnificence. [88] The accidents to which the precarious
subsistence of the city was continually exposed in a winter navigation,
and an open road, had suggested to the genius of the first Caesar the
useful design, which was executed under the reign of Claudius. The
artificial moles, which formed the narrow entrance, advanced far into
the sea, and firmly repelled the fury of the waves, while the largest
vessels securely rode at anchor within three deep and capacious basins,
which received the northern branch of the Tyber, about two miles from
the ancient colony of Ostia. [89] The Roman Port insensibly swelled
to the size of an episcopal city, [90] where the corn of Africa was
deposited in spacious granaries for the use of the capital. As soon as
Alaric was in possession of that important place, he summoned the
city to surrender at discretion; and his dema