Manifest Destiny and Westward Expansion

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Manifest Destiny and Westward Expansion

Manifest Destiny was the belief that it was America's destiny to expand across the entire continent and that everything between the Atlantic and Pacific Oceans should be part of the United States.

This idea motivated people to leave the places they once knew and head west in search for greater opportunities.

As more people headed west, the American government looked to make that land a part of the United States. This came through a variety of treaties, purchases, and conflicts throughout the 1800s. 

America's first major land acquisition was The Louisiana Purchase in 1803. The U.S. bought over 828,000 square miles of land from France for $15 million. This doubled the size of the United States.

Exploration and settlement began immediately after the purchase, and President Thomas Jefferson commissioned Lewis and Clark to map out the territory and find a water route to the Pacific Ocean. 

Manifest Destiny and Westward Expansion

The Florida Territory was later acquired in 1819 with the Adams-Onis Treaty. In this agreement, Spain ceded its remaining province of Florida to the U.S. and set the boundary of Mexico.

Texas was originally part of Mexico, but in 1836 Texans revolted and gained their independence to form the Republic of Texas.

At the time, the majority of settlers in Texas favored joining the United States. However, Texas was a large slave-holding region and there was a delicate balance of pro- and anti-slavery factions in Congress.

It took until 1845 for an annexation bill to be approved and signed by President John Tyler. Texas then became the 28th state in 1846.

Later that year, Americans living in California also rebelled against the Mexican government. They briefly created the Bear Flag Republic before war between the U.S. and Mexico broke out in April 1846.

The war, also over a disputed border of Texas, lasted until 1848 when the Treaty of Guadalupe Hidalgo was signed.

The treaty set the border between Texas and Mexico at the Rio Grande River. It also required Mexico to cede 55% of its territory, including the present-day states of California, Nevada, Utah, New Mexico, and most of Arizona and Colorado.

Lastly, the Oregon Territory had been claimed by several European nations. A treaty between Great Britain and the U.S. ultimately divided the territory between them. The Oregon Treaty of 1846 gave Britain the land north of the 49th parallel and the U.S. the land south of it, including the present-day states of Oregon, Washington, and parts of Idaho, and Wyoming. 

It was unorganized until becoming an official territory in 1848. Many settlers traveled on the treacherous Oregon Trail to find a new home there and elsewhere in the west.

Oregon officially became America's 33rd state in 1859.

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