An impost is another name for a tariff or a customs duty which is imposed upon imports that are being brought into and occasionally out of a nation. An impost is a fee that can be charged by a government in order create a general revenue regarding goods being brought into the nation.
This type of tax was extremely important during a time when trading was the primary way of business throughout the World. Nations would often put an impost or a tax onto goods being brought in, as a way to ensure the legality of the trade, and to secure money for the government.
Impost is used as a way to protect the domestic markets that are found within a nation.
By charging a tax on goods being brought into a nation, the government is regulating what is being brought in, and the frequency of the occurrence. This is helpful for nations who have a rich surplus of goods.
However, a tax on goods that are not produced in the nation is also beneficial, because it creates steady revenue for the nation who requires the goods, and allows for an established business relationship for the nation that has the goods to provide.
Tax that is imposed on goods can often be used to help maintain the ports, travel ways, and military that is used for these types of trading and acquisition endeavors. Impost has been and continues to be an important and ever-changing aspect of business between nations.