Another good graphic from "A history of commerce, 1907" - before and after the age of explorers (mid-15th century).
Geographic discoveries of the 15th century provided another incentive for the Northern Europeans to break away from Catholicism:
The non-Christian world was divided between these two powers by a papal decree which gave to Portugal Africa and Asia except the Philippines and to Spain the Americas except Brazil. So long as other European states obeyed papal authority and feared the might of Spain and Portugal, they were bound to respect this division and the first period of discoveries was followed by a series of voyages carried on especially by English and Dutch seeking a passage northeast or northwest through Arctic seas that would enable them to evade the monopoly granted by the Pope.
Major inventions of the 17th and 18th centuries: log and chronometer:
The simple means of the later Middle Ages could give some idea of a vessel's latitude but very little of its longitude. The introduction of the log in the seventeenth century enabled a sailor to measure distance traversed more accurately and the invention of the chronometer in the eighteenth century gave at last a reliable and practical means of determining longitude at sea.