What was the primary outcome of the Treaty of Guadalupe Hidalgo in 1848?

The primary outcome of the Treaty of Guadalupe Hidalgo in 1848 was the significant territorial acquisition by the United States from Mexico. This treaty ended the Mexican-American War, which had been fueled by disputes over territory and the U.S. Manifest Destiny— the belief that the expansion of the United States across North America was both justified and inevitable.

In the treaty, Mexico ceded approximately half of its territory to the United States, including present-day California, Nevada, Utah, Arizona, and parts of Colorado and New Mexico. This acquisition greatly expanded the size of the United States and reinforced its presence on the West Coast, which had strategic importance and was rich in resources.

The other options reflect events or territories that are unrelated to the Treaty of Guadalupe Hidalgo. The Oregon Territory was obtained through a treaty with Great Britain in 1846, not through this treaty. The cessation of hostilities in the War of 1812 is not relevant to this context, as it pertains to a completely different conflict. Additionally, the treaty did not deal with the Canada-U.S. border, which had been established by previous agreements. Thus, the correct answer focuses on the vast territorial gains made by the United States as a result of the treaty.