Why did the Spanish & English settle in the Caribbean in the 15th & 16th centuries?

The first attempt at colonization was made on Roanoke Island on the coast of North America in 1585, by Sir Walter Raleigh. The settlement did not last, and England will not have any tentative exploration and colonization in the Americas until 1604, after the peace  with Spain.

 In 17th century, Great Britain established the first empire, which had its center in the western hemisphere, ie the Caribbean islands and North America.Settling down in the Caribbean was holding Empire strategic naval superiority.It began with the establishment of tobacco plantations in the West Indies and religious colonies located along the coast of North America.

To become a great power, a country must meet three conditions or criteria. First, countries must be the neighbors of worldwide oceans, on considerable length and have access to oceans by an opened sea. Second,countries must  not have powerful neighbors in the immediate vicinity. Finally, they have to have a naval capacity and high military potential of the sea fleet. All these three criteria were met by Britain. Geographic position of this country, combined with its naval force, have secured for Britain the role of world power that it held so long. Both acquisition and especially the preservation of the British Empire, were dependent on ensuring control over the oceans.