The USA paid Denmark $25 million for the Virgin Islands

Christopher Columbus named the islands after Saint Ursula and the 11,000 Virgins (Spanish: Santa Úrsula y las Once Mil Vírgenes), shortened to the Virgins (las Vírgenes). The official name of the British territory is the Virgin Islands, and the official name of the U.S. territory is the Virgin Islands of the United States. 

The Virgin Islands were originally inhabited by the Arawak, Carib, and Cermic, all of whom are thought to have perished during the colonial period due to enslavement, foreign disease, and mass extermination[citation needed] brought by European colonists.

European colonists later settled here and established sugar plantations, at least one tobacco plantation, and purchased slaves acquired from Africa. The plantations are gone, but the descendants of the slaves remain the bulk of the population, sharing a common African-Caribbean heritage with the rest of the English-speaking Caribbean.

In 1916 and 1917, Denmark and the U.S., respectively, ratified a treaty in which Denmark sold the Danish West Indies to the United States of America for $25 million in gold.