Of the 8 territories that were brought under the flag of the united states by 1853, which one do you think was the most important addition to the growth of the united states?

The main territorial area that was purchased in 1853 is now Arizona and New Mexico. The Gasden Purchase bought this area from Mexico for $10 million.

After the Treaty of Guadalupe Hidalgo in 1848, the Rio Grande and Gila River became the border to the south. However, the U.S. wanted more land to the south to continue the expansion of railroads. The railroad companies needed land south of the Gila River.

The 30,000 square mile purchase enabled the South Pacific Railroad to build through that strip of land.

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