 Under the Treaty of Guadalupe Hidalgo (1848), which ended the Mexican–American War, the United States obtained these territories, and in Article VIII guaranteed the rights of Mexican and former Mexican citizens to their property.However, the U.S. Senate in ratifying the treaty eliminated Article 10, which stated that the U.S. government would honor and guarantee all land grants awarded in lands ceded to the United States to citizens of Spain and Mexico by those respective governments.Thus land grants were subject to being proved.