In the early 16th century Spanish explorers founded San Juan, which prospered throughout the colonial period as a trading port. The island’s other colonial settlements, also predominantly coastal, expanded slowly. From the time the United States took possession of the island in 1898 until the mid-20th century, settlement in Puerto Rico was characterized by dispersed rural farmsteads, as well as some large sugarcane plantations, but the commonwealth subsequently became predominantly urban. More than nine-tenths of the population now live in cities and towns, with only scattered settlements in the mountains. The population of the San Juan metropolitan area, which had swelled to about 400,000 people by 1950, had increased an additional threefold by 2000.

A nearly continuous urban area has developed from Caguas to San Juan and along the north coast from Fajardo through San Juan to Arecibo. Ponce on the south coast and Mayagüez on the west are other urban cores. Few places on the island are more than an hour’s drive from a major urban area, each of which sprawls with modern shopping centres and residential developments such as those found in comparably sized cities in the United States.

Ethnic composition

Puerto Rico’s population is ethnically mixed because of centuries of immigration and cultural assimilation. There is little overt racial discrimination, although people of Spanish and other European ancestry are still esteemed among most elite members of society. Between 20,000 and 50,000 Taino Indians inhabited the island when Columbus arrived there in 1493, but European diseases and maltreatment largely decimated them. The Spanish brought only a limited number of African slaves to Puerto Rico compared with other islands in the region because the local plantations remained relatively small and unimportant. Spanish males, who constituted the largest group of immigrants, freely intermarried with indigenous women and Africans. When slavery was abolished in 1873, only about 5 percent of the population was of entirely African ancestry. Some Chinese, Italians, Corsicans, Lebanese, Germans, Scottish, and Irish also found their way to the island in the mid-19th century, a time when the population was growing steadily. Additional immigrants arrived from the United States after 1898, and more than 20,000 Cuban exiles joined them after Fidel Castro came to power in Cuba in 1959. In subsequent decades an even larger number of job-seeking immigrants arrived from the Dominican Republic.

Language and religion

Both Spanish and English are official languages in Puerto Rico, which remains a predominantly Spanish-speaking society. Many English words have been added to the island’s popular lexicon. English is also widely understood, and about one-fourth of Puerto Rican adults speak English fluently.

Puerto Rico’s constitution guarantees freedom of religion. Today about two-thirds of the island’s inhabitants are Roman Catholics, a legacy of its centuries as a Spanish colony. In the 19th century the church’s loyalty to Spain eroded much of its popular support, and after 1898 many Protestant missionaries arrived from the United States, including Pentecostals, Presbyterians, Methodists, Disciples of Christ, and Congregationalists. Adherents to Protestant churches now account for more than one-fourth of the population.

Demographic trends

Health conditions gradually improved in Puerto Rico following its occupation by the United States, contributing to a population explosion that included a 21 percent increase between 1930 and 1940 and a reduction of death rates. The growing population threatened Puerto Rico’s already fragile economy and quality of life because of the island’s rural economy and limited physical resources, including mountainous slopes poorly suited to agriculture. By 1947, when the island’s population reached some 2,110,000, chronic unemployment had triggered an exodus to the United States, where job opportunities were plentiful. In the 1950s, family planning and mass emigration began to slow the island’s population growth markedly, although crowded conditions continued to strain the economy. In the latter part of the 20th century, Puerto Rico was transformed from a rural to an urban society, allowing for a denser population that no longer depended on marginal agricultural lands. By the beginning of the 21st century, the population was nearly double its 1947 level, but the rates of population growth and infant mortality were reduced, and life expectancy and educational achievement had increased, so that Puerto Rican health standards approached those of the United States. Improved conditions in the early 2000s prompted a small return migration from the United States back to Puerto Rico, the rate of which, according to some sources, at times exceeded that of emigration. As the Puerto Rican economy slid into prolonged recession beginning in 2006, however, this trend was reversed and emigration climbed steadily.

Puerto Ricans in the United States

In 1940 only about 70,000 Puerto Ricans lived in the United States, nine-tenths of them clustered in New York City. By 1960 the U.S.-based Puerto Rican population had increased to 887,000 (of which 615,000 were born in Puerto Rico and 272,000 in the United States) and had already begun to disperse throughout the country, although the largest group remained in New York City. By the late 1990s the number of Puerto Ricans in the United States had increased nearly fourfold over the 1960 level to more than 3,000,000, including some 1,200,000 born on the island.

As a result of the growing exodus from Puerto Rico, prompted by the island’s reeling economy in the early 21st century, the number of persons of Puerto Rican birth or origin residing in the United States exceeded the size of the island’s population. Between 2010 and 2014, net migration from Puerto Rico was estimated at 263,000 people. In 2014 alone some 84,000 Puerto Ricans emigrated to the United States, whereas only about 20,000 returned to the island, resulting in a net out-migration of nearly 2 percent of Puerto Rico’s population.

In the 2010s the Puerto Rican population of the United States was concentrated mainly in New York, Florida, New Jersey, Pennsylvania, Massachusetts, Connecticut, California, Illinois, and Texas. Puerto Ricans have carved out a place for themselves in North American society, occupying leading positions in government, business, education, and the arts. Since virtually every Puerto Rican residing in the United States has relatives on the island, there is frequent back-and-forth travel, particularly during summer and Christmas holidays.