05/18/1846 General Zachary Taylor's troops crossed the Rio Grande and occupied the Mexican border town of Matamoros. (By Matthew Pinsker) Source Citation Arthur M. Schlesinger, Jr., ed., The Almanac of American History (New York: Barnes & Noble Books, 1993), 251. Record Data Date Certainty Exact Type Battles/Soldiers Relevance Personal Major Topics Mexican War People Taylor, Zachary Places Matamoros, Mexico Images