Aerarium

Aerarium (from Latin "aes", in its derived sense of "money") was the name (in full, "aerarium stabulum" - treasure-house) given in Ancient Rome to the public treasury, and in a secondary sense to the public finances.

The treasury contained the monies and accounts of the state finances. It also held the standards of the legions; the public laws engraved on brass, the decrees of the Senate and other papers and registers of importance. These public treasures were deposited in the temple of Saturn at the Forum Romanum, on the eastern slope of the Capitoline Hill. During the republic, they were in the charge of the urban quaestors, under the supervision and control of the Senate.

This arrangement continued (except for the year 43 BC, when no quaestors were chosen) until 28 BC, when Augustus transferred the aerarium to two praefecti aerarii, chosen annually by the Senate from ex-praetors. In 23 these were replaced by two praetors (praetores aerarii or ad aerarium), selected by lot during their term of office. Claudius in 44 restored the quaestors, but had them nominated by the emperor for three years. In 56, Nero substituted two ex-praetors selected under the same conditions.

In addition to the common treasury, supported by the general taxes and charged with the ordinary expenditure, there was a special reserve fund, also in the temple of Saturn, the aerarium sanctum (or sanctius). This fund probably originally consisted of the spoils of war. Afterwards it was maintained chiefly by a 5% tax on the value of all manumitted slaves. This source of revenue was established by a lex Manlia in 357. This fund was not to be touched except in cases of extreme necessity.

Under the emperors, the Senate continued to have at least the nominal management of the aerarium, while the emperor had a separate exchequer, called fiscus. However, after a time, as the power of the emperors increased and their jurisdiction extended until the Senate existed only in form and name, this distinction virtually ceased.

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