51st state
Guam (formally the Territory of Guam) is an unincorporated and organized territory of the United States. Located in the western Pacific Ocean, Guam is one of five American territories with an established civilian government.
List of U.S. states and territories by historical population
As the United States has grown in area and population, new states have been formed out of U.S. territories or the division of existing states. The population figures provided here reflect modern state boundaries. Shaded areas of the tables indicate census years when a territory or the part of another state had not yet been admitted as a new state. As of 2019, 6 regions of the U.S. (the District of Columbia, American Samoa, Guam, the Northern Mariana Islands, Puerto Rico and the U.S. Virgin Islands) remain non-states.