How did the eastern Samoan islands become part of the United States?

The eastern Samoan islands became part of the United States through a combination of international diplomacy and formal agreements with local leadership.

The process began in 1878 when the United States signed a treaty to establish a naval station in Pago Pago Harbor. Following years of colonial rivalry and internal factionalism, an 1899 agreement between the United States, Germany, and Great Britain formally divided the Samoan archipelago, assigning the eastern islands to the United States.12

Following this international partition, the islands were incorporated through the formal cession of land by local chiefs. By 1904, all of the eastern islands had been ceded to the United States. Although the U.S. Navy administered the territory starting in 1900, the U.S. Congress did not formally accept these deeds of cession until February 20, 1929.1