The Mexican War briefly started with the annexation of Texas to the United States early in 1846. This is also known as the American-Mexican War. There was a disagreement about Texas’ western boundary, as Mexico still considered it its territory. Mexico complained of encroachment upon her territory, and hostilities began with the battle of Palo Alto on May 8. They ended with the peace treaty concluded at Guadalupe Hidalgo, near Mexico, on February 2, 1848.
Among the most prominent figures were President Polk, under whose administration annexation was made possible, and General Zachary Taylor, who was chief in command in the field at the beginning of the war and was elected Polk’s successor. Illinois contributed more than its full troop quota to the struggle. On May 13, 1846, war was declared.
On May 25, 1846, Governor Ford issued his proclamation calling for the enlistment of three infantry regiments, the state’s assessed quota. The response was prompt and general. Alton was the rendezvous, and Col. (afterward General) Sylvester Churchill was the mustering officer.
The regiments mustered in were commanded, respectively, by Col. John J. Hardin, Col. Wm. H. Bissell (the future governor), and Col. Ferris Forman. An additional twelve months’ regiment (the Fourth) was accepted under the command of Col. E. D. Baker, who later became a United States Senator from Oregon, and fell at the battle of Ball’s Bluff in October 1861. A second call was made in April 1847, when Illinois sent two more regiments for the war towards the Mexican frontier. These were commanded by Col. Edward W. B. Newby and Col. James Collins. Independent companies were also submitted and accepted.
Besides, some 150 volunteers joined the regiments already in the field. The leaders of independent companies were Capts. Adam Dunlap, of Schuyler County; Wyatt B. Stapp, of Warren; Michael K. Lawler, of Shawneetown; and Josiah Little. Col. John J. Hardin, of the armed forces, was killed at Buena Vista. The official mortuary list includes many names of Illinois’ finest and bravest sons. After participating in the battle of Buena Vista, Illinois troops participated in the triumphal entry into Mexico on September 16, 1847.
They (in connection with those from Kentucky) were especially praised in General Taylor’s official report. The Third and Fourth regiments won distinction at Vera Cruz, Cerro Gordo, and Mexico. At the second of these battles, General Shields suffered severe (and, for a time, mortally wounded) wounds. Colonel Baker succeeded Shields, led a gallant charge, and turned the day around at Cerro Gordo. As mentioned by General Scott in his official report, there were Colonel Forman, Major Harris, Adjutant Fondey, Capt. J. S. Post, and Lieutenants Hammond and Davis.
All the Illinois troops were mustered out between May 25, 1847, and Nov. 7, 1848, the independent companies being the last to quit the service. The total number of volunteers was 6,123, of whom 86 were killed and 160 wounded, 12 of whom died of their wounds. Gallantry in the Mexican War soon became a passport to political preferment, and some of the brave soldiers of 1846–47 subsequently achieved merited distinction in civil life.
Many also became distinguished soldiers in the War of the Rebellion, including such names as John A. Logan, Richard J. Oglesby, M. K. Lawler, James D. Morgan, W. H. L. Wallace, B. M. Prentiss, W. R. Morrison, L. F. Ross, and others. The cost of the war, with §15,000,000 paid for the territory annexed, is estimated at 166,500,000. The extent of territory acquired is nearly 1,000,000 square miles—considerably more than the whole of the present Republic of Mexico territory.