As long as we define “early 1800s” to include the entire first half of the 19th century, the idea of manifest destiny had a huge impact on Mexicans and Native Americans. In both cases, it deprived them of their land and, to some degree, their independence.
During much of the early 1800s (and even after the Civil War), the idea of manifest destiny was used to justify clearing the Native Americans from everywhere that white Americans wanted to be. The idea was that the Americans were racially and culturally superior to the Native Americans. Therefore, they deserved the land more than the Natives did and they had the right to take it. The same logic applied to taking land from Mexico, as was done in the Mexican-American War.
Once the lands were taken from these groups, their independence was compromised. The Native Americans were pushed onto reservations where they were essentially wards of the federal government. Mexicans who remained on what was now US soil often lost their land and were treated as second class citizens in their new country.
In these ways, both Mexicans and Native Americans were harmed by the ideology of manifest destiny.
Westward expansion and manifest destiny had a very negative effect on the Mexicans and on the Native Americans. As Americans wanted to expand westward, they continued to view the Native Americans as being in the way and holding back the progress of our country. In the 1830s, the Native Americans were forcibly removed from their lands east of the Mississippi River to lands west of the Mississippi River. Many Native Americans died as a result of the forced relocation, which often is referred to as the Trail of Tears. As Americans began to expand beyond the Mississippi River, Americans again viewed the Native Americans as holding back the progress of our country. New policies were developed placing Native Americans on reservations. These policies disrupted and, in some cases, destroyed their way of life. These policies were made with the interests of the Americans in mind, not with the interests of the Native Americans in mind. Westward expansion and manifest destiny were not positive events for the Native Americans.
Mexicans were also negatively impacted by these policies. We wanted to gain control of the lands Mexico controlled in the southwest. As a result of a border dispute we had with Mexico regarding the border of Texas, we went to war against Mexico in 1846. As a result of winning this war, known as the Mexican-American War, we got the lands that today make up the southwest part of our country. We also established the Rio Grande River as the border between Texas and Mexico. Westward expansion and manifest destiny negatively impacted the Mexicans.
Both the Native Americans and the Mexicans were impacted by these concepts in another way. As Americans moved westward, they brought diseases with them to which the Native Americans and the Mexicans had no immunity. Many Native Americans and Mexicans contracted these diseases and died from them.
Both westward expansion and manifest destiny were very detrimental to the Mexicans and the Native Americans.
Westward Expansion began with the purchase of new territory by President Thomas Jefferson from the French administration. This territory stretched from Canada to New Orleans and from the Mississippi River to the Rocky Mountains. The point of this purchase, according to the President’s belief, was that in order to protect their liberty the American people had to acquire land to enhance farming and to sustain their population they had to continue expanding their territory. However, through his purchase the Native Americans lost their protection and their rights to the property were infringed on by the new owners. In 1829 President Andrew Jackson established a policy that would forcibly evict the Indian Natives, furthering the Westward Expansion. In 1845, John O’Sullivan came up with “Manifest destiny”, an ideology that supported the Westward Expansion. Continued expansion and Manifest destiny led to the American-Mexican war and eventually Americans annexed Texas and established boundaries on Mexican territory.