Palo Alto order of battle explained

The following units and commanders fought in the Battle of Palo Alto on May 8, 1846, during the Mexican–American War.

U.S. Army

Unit type
Infantry	3rd U.S. Infantry 4th U.S. Infantry 5th U.S. Infantry 8th U.S. Infantry 2nd U.S. Artillery (battalion, serving as infantry)
Mounted units	2nd U.S. Dragoons
Artillery	Duncan's Battery (four 6-pounders) Ringgold's Battery (four 6-pounders) Heavy Battery (two 18-pounders)

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