Geographical discovery and/or accurate mapping were not objectives of the 5,500-mile trek into northern Mexico made from June 1846 to June 1847 by Colonel Alexander W. Doniphan and his First Regiment of Missouri Mounted Volunteers. The somewhat crude and simple maps published in the accounts of the expedition make this clear. At the beginning of the war they accompanied Kearny's "Army of the West" along the Santa Fe trail to New Mexico where they remained behind to garrison the newly conquered territory. In December, Doniphan and his men advanced down the Rio Grande through the dry Jornada del Muerto (Journey of Death) to El Paso del Norte, defeating a Mexican force along their way at Brazito. In February 1847, they continued south into Chihuahua and fought another battle at Sacramento before taking Chihuahua City on March 2. From there they continued southeast to Parras and Saltillo before heading back north along the route Taylor's army had earlier taken into northern Mexico. From the port of Matamoros they returned to Missouri by water. The map in Edward's book here shows X's where the Missourians fought Mexicans or Indians.
Joseph G. Dawson III, "Doniphan's March," in Frazier, ed., United States and Mexico at War, pp. 133-135.
