Guam is a US territory in the Micronesia subregion of the western Pacific Ocean that is unified but unincorporated. It is the United States' westernmost point and territory; in Oceania, it is the largest and southernmost of the Mariana Islands, as well as Micronesia's largest island. The capital of Guam is Hagta, and Dededo is the most populous city. Guamanians are naturalized citizens of the United States. The CHamoru, formerly known as the Chamorro, are indigenous Guamanians who are related to Austronesian tribes from Indonesia, the Philippines, Taiwan, Micronesia, and Polynesia. Guam has a population of 168,801 people as of 2021. Chamorus are the largest ethnic group on the multi-ethnic island, but they are a minority. The area is 210 square miles in size, with a population density of 775 people per square mile. Around 3,500 years ago, the Chamoru people arrived on the island. On March 6, 1521, while serving for Spain, Portuguese explorer Ferdinand Magellan became the first European to visit the island. In 1668, Spain founded a colony on Guam. Guam was an vital stopover for the Spanish Manila Galleons between the 16th and 18th centuries. Guam was conquered by the United States on June 21, 1898, during the Spanish–American War. Spain ceded Guam to the United States on April 11, 1899, under the Treaty of Paris, signed on December 10, 1898. Guam, along with Wake Island in Micronesia, American Samoa and Hawaii in Polynesia, and the Philippines, was one of five American territories in the Pacific Ocean prior to WWII. Guam was seized by the Japanese on December 8, 1941, just hours after Pearl Harbor was attacked, and they occupied the island for two and a half years. Guamanians were subjected to forced labour, imprisonment, torture, and execution during the occupation. On July 21, 1944, American forces recaptured the island, which is now known as Liberation Day. Guam's economy has been largely funded by tourism and the United States military, for which Guam is a significant strategic asset. An unofficial but often used territorial slogan is "Where America's Day Begins," referring to the island's proximity to the International Date Line. Guam is one of the United Nations' 17 non-self-governing territories, and has been a member of the Pacific Community since 1983.