American Samoan is a group of islands in the South Pacific Ocean that lie about halfway between Hawaii and New Zealand and about 100km east of the island country of Samoa, which is part of the same archipelago, ethnicity and culture.
American Samoa is an unincorporated territory of the United States of America. The citizens of American Samoa are US "nationals" and not US "citizens," but they are allowed to travel freely between American Samoa and the US mainland. They are not required to obtain green cards or visas to stay or work in the United States, and they are allowed to serve in the US armed forces (and often do). There are some ways that American Samoa's special status as an unincorporated territory has interesting legal consequences. The US Constitution is not necessarily the supreme law of the land in American Samoa, and Samoan cultural norms, in particular those related to the ownership of property and public displays of religion, actually trump certain well-settled US constitutional rights in American Samoa.
The main city is Pago Pago but the smaller Fagatogo is the constitutionally designated seat of government. The governor's office is located in the village of Utulei, located on the opposite side of Fagatogo from Pago Pago.