America in the 1840s was a rapidly expanding and growing nation. With this expansion came the notion that America should share its free form of federal government with the rest of the world. This ardent conviction was the basis of the ideology called Manifest Destiny. If enlightening the world was the goal, then expansion was the means. Although the general consensus among Americans was that Manifest Destiny was a kindly movement, it was in fact aggressive, racist, and imperialistic. The Manifest Destiny was driven by these factors and pursued at the expense of others. Some examples of this twisted ideology are the American acquisition and settlement of the Oregon country, America causing the Texan subversion of Mexico, and the war between America and Mexico.
American expansion into the Oregon country was a crusade to convert the native population to Protestant Christianity, bring in more American settlers, and to eventually annex the area to America. The Oregon country consisted of what are now the states of Oregon, Washington, Idaho, and parts of Montana, Wyoming, and British Columbia. This area had been jointly occupied by America and Britain since 1818, after the two nations signed a treaty ending their dispute over the territory. However, American interest in the area sparked in the 1830s, and by the 1840s American presence in the area was significantly greater than the British. This interest was mainly grounded in placing missionaries in Oregon to convert Native Americans to Christianity, and in stopping Catholic Canadian missionaries from operating in the same area, which was seen as a threat to eventual American annexation of the territory. When the Native Americans rejected Christianity, the missionaries spitefully encouraged Americans to settle in the tribes" lands. The settlers brought an epidemic of measles that decimated the native population. This American expansion continued unhindered, and by the middle of the 1840s, Americans were not only well entrenched in the Oregon territory, but they were also pushing for the annexation of the territory to the United States.