Guam was captured by a country.
Guam ( [ ˈɡwɑːm ] or [ ˈɡwɒm ] Chamorro : Guåhån [ ˈɡʷɑhɑn ] formally the Territory of Guam ) is an unincorporated and organized territory of the United States . On December 7 , 1941 , hours after the attack on Pearl Harbor , Guam was captured by the Japanese , who occupied the island for thirty months .