Lesson by:
Margaret ‘Peg’ Hill, Ph.D.
Director, SCORE History-Social Science

Treaties are legal documents showing agreements between countries. Treaties at the end of wars are very important because they lay out the terms of the peace. The Treaty of Guadalupe Hidalgo ended the Mexican American War 1846-48 and set up new boundaries for the United States and Mexico. These maps show the changes in the U.S. –Mexican boundaries

As a result of these new boundaries many people who had been citizens of Mexico were now living on land owned by the United States. These people were very concerned about what would happen to them.

According to the treaty what happened to these Mexican land owners who were now living in U.S. territory? Article VIII of the Treaty of Guadalupe Hidalgo set up an agreement with the Mexican government that Mexican citizens who owned and lived on land that had become part of the U.S. under the Treaty could…

  • remain citizens of Mexico or become citizens of the U.S.
  • keep their land or sell it without penalty

Because treaties are legal documents, the language and words in them are very formal and precise. This makes them difficult for average people to read. For Mexicans with land in what was now the U.S. and American citizens who wanted to settle on or buy land in California, it was important for them to read Articles VIII of the treaty carefully and be able to explain it or summarize it for other people.

Below is a copy of Article VIII with many difficult words underlined and briefly defined on another page. Read this section of the treaty aloud as a class and discuss the new words.


Mexicans now established in territories previously belonging to Mexico, and which remain for the future within the limits of the United States, as defined by the present treaty, shall be free to continue where they now reside, or to remove at any time to the Mexican Republic, retaining the property which they possess in the said territories, or disposing thereof, and removing the proceeds wherever they please, without their being subjected, on this account, to any contribution, tax, or charge whatever.

Those who shall prefer to remain in the said territories may either retain the title and rights of Mexican citizens, or acquire those of citizens of the United States. But they shall be under the obligation to make their election within one year from the date of the exchange of ratifications of this treaty; and those who shall remain in the said territories after the expiration of that year, without having declared their intention to retain the character of Mexicans, shall be considered to have elected to become citizens of the United States.

In the said territories, property of every kind, now belonging to Mexicans not established there, shall be inviolably respected. The present owners, the heirs of these, and all Mexicans who may hereafter acquire said property by contract, shall enjoy with respect to it guarantees equally ample as if the same belonged to citizens of the United States.

For the full treaty see