Westward expansion

The United States of America was created on July 4, 1776, with the declaration of independence of thirteen British colonies. Since then, it has expanded across North America and the seas, growing from the thirteen original states to fifty states and many territories from the western Pacific Ocean to the Caribbean Sea.

The capital was not specifically established; at the time, the Continental Congress met in Philadelphia.

Many states had vaguely defined and surveyed borders; these are not noted as contested in the maps unless there was an active dispute. The borders of North Carolina were particularly poorly surveyed, its border with South Carolina having been done in several pieces, none of which truly matched the spirit of the charter, and its border with Virginia was only surveyed roughly halfway inland from the sea.

Several northeastern states had overlapping claims: Connecticut, Massachusetts, and New York all claimed land west of their borders, overlapping with each other and with a sizable claim by Virginia. Of the three, only Connecticut seriously pursued its claims, while Virginia is considered to have had the most legitimate claim to the vast northwest, dividing it into counties and maintaining some limited control.

The entirety of the new United States was claimed by Great Britain. Of particular note are Machias Seal Island and North Rock, two small islands off the northeast coast which remain disputed up to the present.

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