Why did the British use the system of Mercantilism?

The British Empire and other strong European powers adopted the economic system called Mercantilism in the belief that such a system would further their national prosperity. Under this system, England had to attract the maximum amount of gold and silver, since wealth is measured by these metals. England also had to export more than it imported and receive gold and silver as payment for the difference between the payment system. In order to ensure that exports would have a strong base, it would subsidize domestic industry with awards for exporting as much as was possible. Imports would be discouraged by hifg tariffs on such imports that tried to compete with homeland industry. The acquisition of overseas colonies would assure a market for the homeland exports. And, provide an inexpensive source of raw materials, and some gold and silver as well. To keep the colony markets open to homeland exports, restrictions on the colony imports would handle that. Forbid trade with rival European nations as well.