Which Roman inheritance tax, introduced by Augustus, charged one-twentieth of an estate?

The Roman inheritance tax introduced by Augustus and set at one-twentieth of an estate was the vicesima hereditatium.

Augustus established the tax in 6 CE, creating a regular source of revenue for the military treasury, or aerarium militare. The Latin name means “one-twentieth of inheritances,” reflecting its 5% rate. It applied mainly to inheritances and legacies, although close relatives and some small estates received exemptions.

The tax was collected through a network of officials and required legal documentation of estates. It should not be confused with the vicesima manumissionum, a separate 5% tax on the manumission of enslaved people. Roman taxation also included land, provincial tribute, customs duties and sales taxes, so “Roman tax” is not a single specific term.