The United States of America Territorial Expansion

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The U.S. is the 3rd largest country globally, but this country was not always like this.

The 1803 Louisiana Purchase doubled the young American republic’s size, just twenty years after it got independence from Britain Empire. Then the country continued to grow in size.

The 1st great expansion of the country came with the Louisiana Purchase of 1803, which doubled the US territory but brought it into minor conflict with the colonies of Spain which eventually resulted in the acquisition of Spanish Florida.

Webster-Ashburton Treaty of 1842 with Britain split the disputed territory in Maine and New Brunswick and finalized the border with Canada, including the disputed Indian Stream territory.

The annexation of the Republic of Texas in 1845 led directly to the Mexican–American War, after which the victorious United States obtained the northern half of Mexico’s territory (1846), including what was quickly made the state of California.

Texas Annexation was annexed in 1845, New Mexico was captured by the U.S. Army in 1846.

Oregon politicians hoped to continue Oregon’s political evolution into an independent nation, but the pressure to join the U.S. would prevail by 1848, four months after the Mexican–American War.

A map of the historical territorial expansion of the U.S.

America’s territorial expansion from the 19th Century to the 21st Century

The US States by Order of Admittance to the Union, by decade

Date of creation of every 3142 US counties

States that at one time were the largest state by area in the Union

How the US population grew can be found here.