On 13 May 1846, the United States Congress declared war against Mexico. Commodore David Connor commanded the US Navy forces and during the war he was responsible for amphibious operations against several coastal towns, notably the landing of the US Army at Vera Cruz, which was the largest US amphibious operation at that time. In April 1847, Commodore Matthew C. Perry relieved Connor. On 2 Feb 1848, the Treaty of Guadalupe Hidalgo was signed ending hostilities.

James K. Polk, 11th President of the United States, 1845-1849. Artwork on stone by A. Newsam. Lithograph by P.S. Duval, Philadelphia, Pennsylvania. Library of Congress: LC-USZC4-2115.

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