19th century American Southwest

Manifest Destiny: Manifest Destiny was an ideology prevalent in 19th-century America that argued for the expansion of American settlers westward, including into the American Southwest.

Mexican-American War: The Mexican-American War was a conflict between Mexico and the United States from 1846 to 1848. It resulted in significant territorial changes in favor of the U.S., including acquiring much of what is now the American Southwest.

Transcontinental Railroad: The Transcontinental Railroad was a monumental engineering project completed in 1869 that connected the eastern and western coasts of the United States. Its construction had implications for economic growth and settlement in the American Southwest.