Chuuk State (; also known as Truk) is one of the four states of the Federated States of Micronesia (FSM). It consists of several island groups: Nomoneas, Faichuuk, the Hall Islands, Namonuito Atoll (Magur Islands), Pattiw (Western Islands), and the Mortlock Islands. Chuuk is by far the FSM's most populous state, with 33,885 inhabitants on 120 square kilometers (46 square miles). Chuuk Lagoon is where most people live. Weno island, in the lagoon, is Chuuk's state capital and the country's biggest city. Since 2015 there has been a proposed referendum on independence, which has been repeatedly postponed.
Chuuk was first settled by Austronesians, believed to be from the Lapita culture of Island Melanesia. Archaeological evidence indicates that islands of Feefen and Wééné Islands had human settlements in the second and first century BCE. Later evidence indicates that widespread human settlements appeared in Chuuk during the 14th century CE, as the Chuukese culture was formed.
The first sighting recorded by Europeans was made by the Spanish navigator Alvaro de Saavedra on board the Florida during August or September 1528. They were later visited by the Spaniard Alonso de Arellano on 15 January 1565 on board the galleon patache San Lucas.
As part of the Caroline Islands, Truk was claimed by the Spanish Empire, which struggled to control the islands in the late 19th century. The Chuuk Lagoon was then inhabited by Chuukese people (an Austronesian group) that participated in intermittent wars, as well as a small population of foreign merchants and missionaries, mostly linked to the Catholic Church. Spanish control over the islands was in part nominal. The Spanish stopped to raise a flag over Chuuk in 1886, and returned in 1895 as part of an attempt to assert control and negotiate peace between the tribes of Chuuk. No major Spanish settlement was established and traditional life continued until the German colonial era.
The Caroline Islands were sold to the German Empire in 1899, after Spain withdrew from the Pacific after the Spanish–American War in which it lost its main colony in Asia, the Philippines. Germany incorporated the territory into its domain in the German New Guinea.
During World War I, the Imperial Japanese Navy was tasked with pursuing and destroying the East Asia Squadron of the Imperial German Navy and protecting the shipping lanes of Allied trade in the Pacific and Indian Oceans. During the course of this operation, the Japanese navy seized German possessions in the Mariana Islands, the Carolinas, the Marshall Islands and Palau groups by October 1914. Chuuk then became a possession of the Empire of Japan under the South Seas Mandate of the League of Nations after the defeat of Germany in World War I.
Chuuk was one of six districts of the Trust Territory of the Pacific Islands (TTPI) which were administered by the United States under charter from the United Nations from the end of the Second World War to the mid-1980s. The termination of U.S. administration of the Chuuk, Yap, Kosrae, Pohnpei, and Mariana Islands districts of the TTPI occurred on 3 November 1986.
The Federated States of Micronesia, including Chuuk, Yap, Kosrae, and Pohnpei, was established in 1979 and signed a Compact of Free Association with the U.S. (effective 3 November 1986).
As of recent times, Chuuk has been pushing harder for independence. An independence referendum was originally scheduled to coincide with federal elections on 3 March 2015, but was pushed back to 5 March 2019. The independence referendum was further pushed back to March 2022, with a date to be announced, while the constitutional legality of the proposed secession is determined.
To the west is Yap State. To the east are Pohnpei State and Kosrae State is further east.
The main population center of Chuuk State is the Chuuk Lagoon, a large archipelago with mountainous islands surrounded by a string of islets on a barrier reef. The two major geographical and dialectic divisions of the Chuuk Lagoon are Faichuuk, the western islands, and Namoneas, the eastern islands.
Chuuk State also includes several more sparsely populated "outer island" groups, including the Mortlock Islands to the southeast, the Hall Islands (Pafeng) to the north, Namonuito Atoll to the northwest, and the Pattiw Region to west. The Pattiw Region is of particular interest in that it has some of the most traditional islands in the Pacific and is culturally related to outer islands of Yap. This group includes the islands of Pollap, Tamatam, Poluwat, and Houk. There are still traditional master navigators—Poluwat and Pollap are considered to have some of the best navigators and ocean-going outrigger canoes in the Pacific. In the islands of the Pattiw Region, and some of the Islands of Yap, are the last two remaining schools of navigation, Weriyeng and Faaluush. Visiting the Pattiw Region in the west, however, is difficult due to the lack of reliable transportation. Houk probably has the most accessible airstrip in the Pattiw Region, with planes landing every one or two weeks.
The state shares its longitude with Sydney, Australia, namely the eastern portion of the city including the CBD.
On 2 July 2002, heavy rains from Tropical Storm Chataan caused more than thirty landslides that killed forty-seven people and injured dozens of others, in the state's deadliest weather disaster. The landslides occurred throughout the day, some within just minutes of each other.
Chuuk is the most populous of the FSM's states. At the census held on 1 April 2000, it had 53,595 inhabitants, compared with 34,486 for Pohnpei State, 11,241 for Yap State and 7,686 for Kosrae; at the census held on 4 April 2010, it had 48,654 inhabitants, compared with 36,196 for Pohnpei State, 11,377 for Yap State and 6,616 for Kosrae. In 2023, the population of Chuuk State, while still the largest of the four states, decreased by about 30% from the 2010 population to 33,885 inhabitants.
The majority of the state's population is affiliated with Christianity as a result of the activity of missionary groups first from Spain and then from Germany and the United States. Catholicism was introduced during the Spanish colonization period, followed by the arrival of various Protestant groups. The main religious building in the state is the Immaculate Heart of Mary Cathedral in Tunnuk, Weno, which is under the jurisdiction of the Diocese of the Caroline Islands (Diocese Carolinensium) suffragan of the ecclesiastical province of Agaña in Guam. Other churches in the state include Sacred Heart Church on Lekinioch Island, Christ the King Church in Neiwe, Houk Catholic Church, Holy Family Church in Weno, St. Ignatius Church in Fonoton, among others.
The people of the country speak the Chuukese language, a Micronesian language.
The USA East Province of the Society of Jesus (the Jesuits) maintains a mission school on the island of Weno in Chuuk. Xavier High School is housed at the former Japanese communications center. It is a coeducational institution, drawing students from all the island groups of the Federated States of Micronesia, as well as Palau and the Marshall Islands. Teachers are both Jesuit and lay and come from Micronesia, the U.S., Indonesia, Japan, and Australia.