Puerto Rico, officially the Commonwealth of Puerto Rico, is an unincorporated territory of the United States, located in the northeastern Caribbean east of the Dominican Republic and west of both the United States Virgin Islands and the British Virgin Islands. The main island of Puerto Rico is, by land area, the smallest of the Greater Antilles. With around 3.6 million people, it ranks third in population among that group of four islands. The Roman Catholic Church was brought by Spanish colonists and gradually became the dominant religion in Puerto Rico. By virtue of its long political association with the United States, is the most Protestant of Latin American countries, with a Protestant population of approximately 33 to 38 percent, the majority of whom are Pentecostal.