September 20, 1846 - September 24, 1846
On September 20, 1846, General Zachary Taylor led a group of 6,500 U.S. soldiers and volunteers to attack the northern Mexico city of Monterrey. The city was well-fortified and protected by artillery installations and 10,000 Mexican soldiers under the command of General Pedro de Ampudia. Taylor approached the city from the east, while sending William Worth on a flanking movement to the southwest to cut off the Mexican army's escape route. Worth succeeded in doing so, and gained steady ground against Mexican hilltop fortifications, seizing Federation Hill on the 21st and the Archbishop's Palace the following day. On the evening of the 22nd Ampudia ordered his troops to take up defensive positions within the city, setting the stage for bitter house-to-house fighting on the 23rd. On the morning of September 24, U.S. troops were preparing to renew their assault when Ampudia asked for a parley. Taylor and Ampudia signed an eight-week armistice, and Taylor allowed Ampudia's troops to evacuate the city, taking with them their weapons and one six-gun battery.