The largest and most populous of the Mariana Islands in the Western Pacific, Guam (13° 28′ n and 144° 44′ e) has an area, including land and water, of 540 sq km (208 sq mi) and is about 48 km (30 mi) long and from 6 to 12 km (4–7 mi) wide. The island is of volcanic origin; in the south, the terrain is mountainous, while the northern part is a plateau with shallow fertile soil. The central part of the island (where the capital, Agana, is located) is undulating country.
Guam lies in the typhoon belt of the Western Pacific and is occasionally subject to widespread storm damage. In May 1976, a typhoon with winds of 306 km/hr (190 mph) struck Guam, causing an estimated $300 million in damage and leaving 80% of the island's buildings in ruins. Guam has a tropical climate with little seasonal variation. Average temperature is 26° c (79° f); rainfall is substantial, reaching an annual average of more than 200 cm (80 in). Endangered species include the giant Micronesian kingfisher and Marianas crow.
The mid-2002 population, excluding transient US military and civilian personnel and their families, was estimated at 160,796, an increase over the 1986 estimate of 117,500. The increase was attributed largely to the higher birthrate and low mortality rate. The present-day Chamorro, who comprise about 37% of the permanent resident population, descend from the intermingling of the few surviving original Chamorro with the Spanish, Filipino, and Mexican settlers, plus later arrivals from the United States, United Kingdom, Korea, China, and Japan. Filipinos (26%) are the largest ethnic minority. English is the official language, although Chamorro is taught in the primary schools. The predominant religion is Roman Catholicism.
The earliest known settlers on Guam were the original Chamorro, who migrated from the Malay Peninsula to the Pacific around 1500 bc. When Ferdinand Magellan landed on Guam in 1521, it is believed that as many as 100,000 Chamorro lived on the island; by 1741, their numbers had been reduced to 5,000— most of the population either had fled the island or been killed through disease or war with the Spanish. A Spanish fort was established in 1565, and from 1696 until 1898, Guam was under Spanish rule.
Under the Treaty of Paris that ended the Spanish-American War in 1898, the island was ceded to the United States and placed under the jurisdiction of the Department of the Navy. During World War II, Guam was occupied by Japanese forces; the United States recaptured the island in 1944 after 54 days of fighting. In 1950, the island's administration was transferred from the Navy to the US Department of the Interior. Under the 1950 Organic Act of Guam, passed by the US Congress, the island was established as an unincorporated territory of the United States; Guamanians were granted US citizenship, and internal self-government was introduced.
The governor and lieutenant governor have been elected directly since 1970. A 15-member unicameral legislature elected for two years by adult suffrage is empowered to legislate on all local matters, including taxation and appropriations. The US Congress reserves the right to annul any law passed by the Guam legislature, but must do so within a year of the date it receives the text of any such law.
Judicial authority is vested in the district court of Guam, and appeals may be taken to the regular US courts of appeal and ultimately to the US Supreme Court. An island superior court and other specialized courts have jurisdiction over certain cases arising under the laws of Guam. The judge of the district court is appointed by the US president; the judges of the other courts are appointed by the governor. Guam's laws were codified in 1953.
Guam is one of the most important US military bases in the Pacific, and the island's economy has been profoundly affected by the large sums of money spent by the US defense establishment. During the late 1960s and early 1970s, when the United States took the role of a major combatant in the Viet-Nam conflict, Guam served as a base for long-range US bombers on sorties over Indochina. In 2001, there were 3,398 active-duty US military personnel stationed on the island.
Prior to World War II, agriculture and animal husbandry were the primary activities. By 1947, most adults were wage earners employed by the US armed forces, although many continued to cultivate small plots to supplement their earnings. Since World War II, agriculture has generally contributed less than 1% of the GNP, partly because a considerable amount of arable land is taken up by military installations. Fruits and vegetables are grown and pigs and poultry are raised for local consumption, but most food is imported. Current fish catches are insufficient to meet local demand.
Tourism has become a major industry and sparked a boom in the construction industry in the mid-1980s. The number of visitors grew rapidly from 6,600 in 1967 to around one million per year in the early 2000s, 90% of whom come from Japan. The stagnation in the Japanese economy since the early 1990s slowed the growth of Guam's tourism sector.
The Guam Rehabilitation Act of 1963 has funded the territory's capital improvement program. Further allocations in 1969 and 1977 provided over $120 million for additional capital improvements and development of the island's power installations. More than $200 million of federal funds were authorized for typhoon relief in 1977–78. Total expenditures by the government of Guam were $431 million in 2000; revenues were $420 million.
Guam's foreign trade usually shows large deficits. The bulk of Guam's trade is with the United States, Micronesia, and Japan.
US income tax laws are applicable in Guam; all internal revenue taxes derived by the United States from Guam are paid into the territory's treasury. US customs duties, however, are not levied. Guam is a duty-free port. In its trade with the US mainland, Guam is required to use US shipping.
Typical tropical diseases are practically unknown today in Guam. Tuberculosis, long the principal killer, was brought under control by the mid-1950s. The Guam Memorial Hospital has a capacity of 192 beds. Village dispensaries serve both as public health units and first-aid stations. In addition, there are a number of physicians in private practice. Specialists from the US Naval Hospital in Guam, assisting on a part-time basis, have made possible a complete program of curative medicine.
School attendance is compulsory from the age of 6 through 16. In 1998/99, 31,860 pupils were enrolled in public elementary and secondary schools. The University of Guam enrolled 3,748 students in 1998/99, and Guam Community College enrolled 4,404 students in the fall of 1998.