Primary factors…

The United States acquired Puerto Rico in 1898 at the end of the Spanish-Cuban-American War and has retained sovereignty over the island ever since. In 1917, the U.S. Congress passed the Jones Act, which made Puerto Ricans citizens of the United States. In 1952, Puerto Rico’s political ties to the Union were formalized as the island became the Estado Libre Asociado (ELA) or the Commonwealth of Puerto Rico.

• Territory: Puerto Rico
• Status: Self-governing territory belonging to the USA
• Full name: Commonwealth of Puerto Rico
• Population: 3.9 million (via UN, 2006)
• Capital: San Juan
• Area: 8,959 sq km (3,459 sq miles)
• Major languages: Spanish, English (both official)
• Major religion: Christianity
• Life expectancy: 71 years (men) 80 years (women)
• Monetary unit: US dollar
• Main exports: Chemicals, foodstuffs, machinery
• GNI per capita: $10,950 (World Bank, 2001)
• Internet domain: .pr
• International dialling code: +1787

Nations Unies, éd. Planification du développement économique et social équilibré. Six monographies [Inde, Pays-Bas, Pologne, Porto Rico, Sénégal, Yougoslavie.]. Département des affaires économiques et sociales. New York: Nations Unies, 1964. p.139

In 1898, as a result of the Spanish-American war, Puerto Rico became a possession of the United States of America. United States jurisdiction has meant, among other things, that Puerto Rico products have had access to United States markets, on a duty-free basis and that excise taxes on Puerto Rican production and customs duties collected by the United States Treasury have been refunded o Puerto Rico. Under the protection of the United States of the United States tariff system, sugar, which was of secondary importance under Spanish rule, grew rapidly until it dominated the economy. It provided employment, investment, transportation, communication, power, banking and others. On the other hand, coffee, which did not gain a protected United States market in exchange for the previously protected European market, lost its primary position in the economy.

Prior to 1940, both internal and external investment was small, being limited to the sugar industry. Needlework achieved some importance but the income it generated was small. There is no doubt that the total income of Puerto Rico rose, but the expansion was limited to one crop, which was insufficient to offset the population increase.

Under the Spanish regime population had grown rapidly. After 1898 the rate of increase continued to riese, so that population was doubling itself every forty years. In 1910 it exceeded the United States rate which was high because of immigration, whereas Puerto Rico tended and still tends to be an area of emigration.

By 1940, in view of the rising rate of population growth, it was necessary for the economy to increase production by 2 per cent a year merely to maintain a constant income per head. What was even more important was that a drastic drop in death rate would soon develop largely as the result fo the new “wonder drugs” which are to be introduced during the Second War World, thus increasing the annual increment in population by about 50 per cent.  […] A converging of political, economic, social and administrative forces during the decade of the 1940’s made possible a sharp break with the stagnation of the past […] and which certainly helped to define what Puerto Rico is today.

Morales Carrión, Arturo. Puerto Rico: a political and cultural history.
New York, N.Y: W. W. Norton, 1983. p. 320

In the cultural evolution evolution of the island, the following factors are of primary importance:

1. The island was a colony of the vas Spanish empire in the New World from 1493 (…) until 1898.
2. (…) The imprint of Spanish literary and artistic trends is evident in the literature, the music, the dances, and he rituals of life and death, love and patriotism.
3. The mixture of Indian, Black, and Spanish elements in the early days of the conquest and colonization enriched the ethnic and the spiritual structure of the population.
4. The language of the people of Puerto Rico is Spanish, and the literature of Puerto Rico is written in Spanish, although many educated Puerto Ricans have learned English and some have written in English, mainly in newspapers and general magazines dealing with political and social problems.
5. English has been taught in the schools of Puerto Rico (…), but (it) has never been the language of Puerto Rico in daily life.
6. To study in depth the cultural spectrum of Puerto Rican life, it is essential to learn Spanish.
7. There is absolute freedom od worship in Puerto Rico (…) Catholic religion predominates.
8. The Treaty of Paris determined the fate of Puerto Rico.
9. The language policy was the core of the cultural struggle throughout the twentieth century.
10. American citizenship was extended to Puerto Ricans during the World War I, in 1917.
11. The traditional political ideas are independence, statehood and commonwealth.

Find out more on Puerto Rico’s country profile by the BBC:

Hispanic, Afro-Caribbean and North American influences meld in Puerto Rico, a self-governing commonwealth that belongs to the United States.

The subtropical Caribbean territory is urbanised, industrialised and relatively prosperous… (continue reading here)