Guam ( GWAHM; Chamorro: Guåhan [ˈɡʷɑhɑn]) is an organized, unincorporated territory of the United States in the Micronesia subregion of the western Pacific Ocean. Guam's capital is Hagåtña, and the most populous village is Dededo. It is the westernmost point and territory of the United States, reckoned from the geographic center of the U.S. In Oceania, Guam is the largest and southernmost of the Mariana Islands and the largest island in Micronesia. As of 2022, its population was 168,801. Chamorros are its largest ethnic group, but a minority on the multiethnic island. The territory spans 210 square miles (540 km2; 130,000 acres) and has a population density of 775 per square mile (299/km2).
Indigenous Guamanians are the Chamorro, who are related to the Austronesian peoples of the Malay Archipelago, the Philippines, Taiwan, and Polynesia. But unlike most of its neighbors, the Chamorro language is not classified as a Micronesian or Polynesian language. Rather, like Palauan, it possibly constitutes an independent branch of the Malayo-Polynesian language family. The Chamorro people settled Guam and the Mariana islands approximately 3,500 years ago. Portuguese explorer Ferdinand Magellan, while in the service of Spain, was the first European to visit and claim the island on March 6, 1521. Guam was fully colonized by Spain in 1668. Between the 17th and 19th centuries, Guam was an important stopover for Spanish Manila galleons. During the Spanish–American War, the United States captured Guam on June 21, 1898. Under the 1898 Treaty of Paris, Spain ceded Guam to the U.S. effective April 11, 1899.
Before World War II, Guam was one of five American jurisdictions in the Pacific Ocean, along with Wake Island in Micronesia, American Samoa and Hawaii in Polynesia, and the Philippines. On December 8, 1941, hours after the attack on Pearl Harbor, Guam was captured by the Japanese, who occupied the island for two and a half years before American forces recaptured it on July 21, 1944, which is commemorated there as Liberation Day. Since the 1960s, Guam's economy has been supported primarily by tourism and the U.S. military, for which Guam is a major strategic asset. Its future political status has been a matter of significant discussion, with public opinion polls indicating a strong preference for American statehood.
Guam's de facto motto is "Where America's Day Begins", which refers to the island's proximity to the International Date Line. Guam is among the 17 non-self-governing territories listed by the United Nations, and has been a member of the Pacific Community since 1983.
Guam is called Guåhan by Chamorro speakers, from the word guaha, meaning 'to have'; its English gloss 'we have' references the island's providing everything needed to live.
Guam, along with the other Mariana Islands, were the first islands settled by humans in Remote Oceania. It was also the first and the longest of the ocean-crossing voyages of the Austronesian peoples, and is separate from the later Polynesian settlement of the rest of Remote Oceania. They were first settled around 1500 to 1400 BC, by migrants departing from the Philippines which was followed by a second migration from the Caroline Islands in the first millennium AD. A third migration wave took place from Island Southeast Asia, likely the Philippines or eastern Indonesia, by 900 AD.
These original settlers of Guam and the Northern Mariana Islands evolved into the Chamorro people, historically known as Chamorros after first contact with the Spaniards. The ancient Chamorro society had four classes: chamorri (chiefs), matua (upper class), achaot (middle class), and mana'chang (lower class). The matua were located in the coastal villages, which meant they had the best access to fishing grounds. The mana'chang were located in the island's interior. Matua and mana'chang rarely communicated with each other. The matua often used achaot as intermediaries.
There were also "makåhna" or "kakahna", shamans with magical powers and "'suruhånu" or "suruhåna", healers who used different kinds of plants and natural materials to make medicine. Belief in spirits of ancient Chamorros called "Taotao mo'na" still persists as a remnant of pre-European culture. It is believed that "suruhånu" or "suruhåna" are the only ones who can safely harvest plants and other natural materials from their homes or "hålomtåno" without incurring the wrath of the "Taotao mo'na." Their society was organized along matrilineal clans.
The Chamorro people raised colonnades of megalithic capped pillars called latte stones upon which they built their homes. Latte stones are stone pillars that are found only in the Mariana Islands. They are a recent development in Pre-Contact Chamorro society. The latte-stone was used as a foundation on which thatched huts were built. Latte stones consist of a base shaped from limestone called the haligi and with a capstone, or tåsa, made either from a large brain coral or limestone, placed on top. A possible source for these stones, the Rota Latte Stone Quarry, was discovered in 1925 on Rota.
The first European to travel to Guam was Portuguese navigator Ferdinand Magellan, sailing for the King of Spain, when he sighted the island on March 6, 1521, during his fleet's circumnavigation of the globe. Despite Magellan's visit, Guam was not officially claimed by Spain until January 26, 1565, by Miguel López de Legazpi. From 1565 to 1815, Guam and the Northern Mariana Islands, the only Spanish outposts in the Pacific Ocean east of the Philippines, were reprovisioning stops for the Manila galleons, a fleet that covered the Pacific trade route between Acapulco and Manila.
Spanish colonization commenced on June 15, 1668, with the arrival of a mission led by Diego Luis de San Vitores, who established the first Catholic church. The islands were part of the Spanish East Indies, and part of the Viceroyalty of New Spain, based in Mexico City. The Spanish-Chamorro Wars on Guam began in 1670 over growing tensions with the Jesuit mission, with the last large-scale uprising in 1683.
Intermittent warfare, plus the typhoons of 1671 and 1693, and in particular the smallpox epidemic of 1688, reduced the Chamorro population from 50,000 to 10,000, and finally to less than 5,000. Up until the late 19th century, Guam was encountered by adventurers and pirates, including Thomas Cavendish, Olivier van Noort, John Eaton, William Dampier, Woodes Rogers, John Clipperton, George Shelvocke and William "Bully" Hayes.
The island became a rest stop for whalers starting in 1823. A devastating typhoon struck the island on August 10, 1848, followed by a severe earthquake on January 25, 1849, which resulted in many refugees from the Caroline Islands, victims of a resultant tsunami. This earthquake was much more powerful than the 8.2 one that occurred on August 8, 1993. After a smallpox epidemic killed 3,644 Guamanians in 1856, Carolinians and Japanese were permitted to settle in the Marianas.
The Marianas and specifically the island of Guam were a stopover for Spanish galleons en route from Acapulco, Mexico to Manila, Philippines in a convoy known as the Galeon de Manila. In the 1818 Spanish Census of the Spanish-Philippines, of which, the Marianas islands was under the governance of the Philippine Islands, it was recorded to have had 7,555 souls and of which there were 160 Spanish soldiers from Spain and Mexico, garrisoning the Marianas.
After almost four centuries as part of the Kingdom of Spain, the United States occupied the island following Spain's defeat in the 1898 Spanish–American War, as part of the Treaty of Paris of 1898. Guam was transferred to the United States Navy control on December 23, 1898, by Executive Order 108-A from 25th President William McKinley.
Guam was a station for American merchants and warships traveling to and from the Philippines, which was another American acquisition from Spain, while the Northern Mariana Islands were sold by Spain to Germany for part of its rapidly expanding German Empire. A U.S. Navy yard was established at Piti in 1899. A United States Marine Corps barracks was established at Sumay in 1901.