PORTŌRĬUM, a branch of the regular revenues of the Roman state,
consisting of the duties paid on imported and exported goods. A
portorium, or duty upon imported goods, appears to have been paid at
a very early period, for it is said that Valerius Publicola exempted
the plebes from the portoria at the time when the republic was
threatened with an invasion by Porsena. The time of its introduction
is uncertain; but the abolition of it, ascribed to Publicola, can
only have been a temporary measure; and as the expenditure of the
republic increased, new portoria must have been introduced. In
conquered places, and in the provinces, the import and export duties,
which had been paid there before, were generally not only retained,
but increased, and appropriated to the aerarium. Sicily, and above
all, Asia, furnished to the Roman treasury large sums, which were
raised as portoria. In B.C. 60 all the portoria in the ports of Italy
were done away with by a Lex Caecilia, but were restored by Julius
Caesar and the subsequent emperors. Respecting the amount of the
import or export duties we have but little information. In the time
of Cicero the portorium in the ports of Sicily was one-twentieth
(_vicesima_) of the value of taxable articles; and it is probable
that this was the average sum raised in all the other provinces.
In the times of the emperors the ordinary rate of the portorium
appears to have been the fortieth part (_quadragesima_) of the value
of imported goods; and at a later period the exorbitant sum of
one-eighth (_octava_) is mentioned. The portorium was, like all other
vectigalia, farmed out by the censors to the publicani, who collected
it through the _portitores_. [VECTIGALIA; PUBLICANI.]