On March 29, 1847, 12,000 US troops captured Vera Cruz, Mexico. From the article:
"Battle of Vera Cruz
The American army undertook its first successful amphibious landing, when under the command of General Winfield Scott, a force of 12,000 landed 3 miles southeast of the city of Vera Cruz on March 9, 1847. He thus successfully outflanked the Mexican army defending the city. They were soon forced to surrender.
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The American Navy’s task on the East coast of Mexico was to blockade the ports of Mexico and try to occupy as many of them as possible. The American fleet was commanded by Commander David Conner. Conners forces occupied a number of ports. Conner then transported General Winfield Scott and 12,000 troops to Vera Cruz. Scott knew he needed to capture Vera Cruz in order to move inland. While his officers recommended a direct assault Scott feared the number of casualties he would incur. Instead On March 9th 1847, he landed his men at a beach at Collado three miles southeast of Vera Cruz. 12,000 men were landed in the United State's first amphibious landing. By the 15th Vera Cruz was surrounded. On March 22 after the town refused to surrender Scott began an cannonade of the town. After twelve days of firing the Mexicans agreed to surrender. American forces occupied the town on March 29th."