M.M. Postan & Eileen Power 
Studies in English Trade in the 15th Century [PDF ebook] 

Of all the activities of the most neglected century in English History, England’s trade has received the least attention in proportion to its importance. It was obviously in the course of the later Middle Ages, and more particularly in the fifteenth century, that there took place the great transformation from medieval England, isolated and intensely local, to the England of the Tudor and Stuart age, with its world-wide connections and imperial designs. It was during the same period that most of the forms of international trade characteristic of the Middle Ages were replaced by new methods of commercial organization and regulation, national in scope and at times definitely nationalistic in object, and that a marked movement towards capitalist methods and principles took place in the sphere of domestic trade. Yet little has been written concerning English trade in this period.First published in 1933, this classic volume goes a long way to fills this gap superbly. There is an abundance of material, and the writers have compiled a statistical analysis of the Enrolled Customs Account from 1377-1482, which provides an essential measure of the nature, volume, and movement of English foreign commerce during the period.