Congress officially approved the name United States of America on September 9, 1776, during the founding period commemorated by America250. The decision changed the wording used in congressional documents and military references.
The Declaration of Independence had already used the phrase United States of America. Before September, however, Congress often referred to the colonies collectively as the United Colonies. The formal naming decision helped establish a common national identity during the Revolutionary War.
The name was not invented entirely in July 1776. It had appeared in earlier colonial and revolutionary writing, including the Declaration itself. Congress's September action made it the official name for the new country in its records.
This change came while the war was still underway and before the Articles of Confederation were completed. The Articles were adopted by Congress in 1777 and later ratified by the states, creating a formal framework for the first national government.