Savage Tribes: Article XI of the Treaty of Guadalupe Hidalgo - 1848

Article XI

Considering that a great part of the territories, which, by the present treaty, are to be comprehended for the future within the limits of the United States, is now occupied by savage tribes, who will hereafter be under the exclusive control of the Government of the United States, and whose incursions within the territory of Mexico would be prejudicial in the extreme, it is solemnly agreed that all such incursions shall be forcibly restrained by the Government of the United States whensoever this may be necessary; and that when they cannot be prevented, they shall be punished by the said Government, and satisfaction for the same shall be exacted all in the same way, and with equal diligence and energy, as if the same incursions were meditated or committed within its own territory, against its own citizens.