Cause and Effect - Manifest Destiny
It is "our manifest destiny to overspread the continent allotted by Providence for the free development of our yearly multiplying millions." John L. O'Sullivan 1845
What were some of the many factors that led Americans to believe that the US was destined to expand across the North American continent? Many felt is as simply the will of God that they spread their wings to the Pacific, and help bring Christianity to the people of the West. Expansion offered greater access to lucrative markets in Asia, such as China and Japan, and the increased trade would benefit the young US. The population was growing due to a high birth rate and immigration, and much of the farmland east of the Mississippi was already claimed. In addition, some Southerners were anxious to enlarge the institution of slavery. Finally, America had the technology and transportation necessary to expand. Put it all together, and Manifest Destiny was a prominent belief of many in the 1840s.
The effects of Manifest Destiny were massive, especially with territorial gains. Few nations had ever expanded so quickly. The US annexed Texas after an revolution, secured the Oregon Country in a treaty with England, and gained all of California (and more) as a result of the Mexican War. The territorial expansion was remarkable, providing the growing US with farmland, waterways, resources, and access to the Pacific for travel and trade. An "American" culture spread across the continent as pioneers moved westward, bringing civilization to a formerly uncivilized place.
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