In the early republic state income was obtained from the rents of the ager publicus. The only direct tax paid by Romans was the tributum, a land and property tax levied in times of emergency. This was abolished on land in Italy in 167 BC as the treasury was enriched through overseas conquests. The tributum continued to be paid by citizens and non-citizens in conquered territory and was an important source of revenue.... New indirect taxes in the empire included portoria (customs). There were also taxes on the sale and manumission of slaves and inheritance taxes, levied at a rate of 5 percent. The inheritance tax was levied on the property of Roman citizens only, and the revenue went to the aerarium militare (military treasury), together with the revenues from the 1 percent tax on auction sales. In the imperial provinces taxes were collected by a procurator, and in senatorial provinces the quaestor was in charge, although publicani (tax collectors or publicans) were used.... In 296 Diocletian introduced a new tax system.