1848-07-04: Treaty of Guadelupe Hidalgo Proclaimed

The treaty was signed on February 2, 1848 and ratified by the United States Senate on March 10 and by Mexico on May 19, 1848.

TREATY OF PEACE, FRIENDSHIP, LIMITS, AND SETTLEMENT BETWEEN THE UNITED STATES OF AMERICA AND THE UNITED MEXICAN STATES CONCLUDED AT GUADALUPE HIDALGO, FEBRUARY 2, 1848; RATIFICATION ADVISED BY SENATE, WITH AMENDMENTS, MARCH 10, 1848; RATIFIED BY PRESIDENT, MARCH 16, 1848; RATIFICATIONS EXCHANGED AT QUERETARO, MAY 30, 1848; PROCLAIMED, JULY 4, 1848.
http://www.yale.edu/lawweb/avalon/diplomacy/mexico/guadhida.htm 

http://en.wikipedia.org/wiki/Treaty_of_Guadalupe_Hidalgo