Answer:
There are about four reasons...
Step-by-step explanation:
Migration of skilled workers to the Dutch Republic
Under the terms of the surrender of Antwerp in 1585, the Protestant population (if unwilling to reconvert) were given four years to settle their affairs before leaving the city and Habsburg territory.[2] Similar arrangements were made in other places. Protestants were especially well-represented among the skilled craftsmen and rich merchants of the port cities of Bruges, Ghent, and Antwerp. More moved to the north between 1585 and 1630 than Catholics moved in the other direction, although there were also many of these. Many of those moving north settled in Amsterdam, transforming what was a small port into one of the most important ports and commercial centres in the world by 1630.
In addition to the mass migration of Protestant natives from the southern Netherlands to the northern Netherlands, there were also influxes of non-native refugees who had previously fled from religious persecution, particularly Sephardi Jews from Portugal and Spain, and later Protestants from France. The Pilgrim Fathers also spent time there before their voyage to the New World.
Protestant work ethic
Economists Ronald Findlay and Kevin H. O'Rourke attribute part of the Dutch ascendancy to its Protestant work ethic based on Calvinism, which promoted thrift and education. This contributed to "the lowest interest rates and the highest literacy rates in Europe. The abundance of capital made it possible to maintain an impressive stock of wealth, embodied not only in the large fleet but in the plentiful stocks of an array of commodities that were used to stabilize prices and take advantage of profit opportunities.
Cheap energy sources
Several other factors also contributed to the flowering of trade, industry, the arts and the sciences in the Netherlands during this time. A necessary condition was a supply of cheap energy from windmills and from peat, easily transported by canal to the cities. The invention of the wind powered sawmill enabled the construction of a massive fleet of ships for worldwide trading and for military defense of the republic's economic interests.
Geography
According to Ronald Findlay and Kevin H. O'Rourke, geography favored the Dutch Republic, contributing to its wealth. They write, "The foundations were laid by taking advantage of location, midway between the Bay of Biscay and the Baltic. Seville and Lisbon and the Baltic ports were too far apart for direct trade between the two terminal points, enabling the Dutch to provide profitable intermediation, carrying salt, wine, cloth and later silver, spices, and colonial products eastward while bringing Baltic grains, fish, and naval stores to the west. The Dutch share of European shipping tonnage was enormous, well over half during most of the period of their ascendancy."
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