customscustoms duties granted since medieval times to the English crown by Parliament. Tonnage was a fixed subsidy on each tun (cask) of wine imported, and poundage was an ad valorem (proportional) tax on all imported and exported goods. Though of separate origin, they were granted together from 1373 and were used for the protection of trade at sea. From 1414 they were customarily granted for life to each successive king
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