California Column The California Column was a force of Union volunteers sent to Arizona and New Mexico during the American Civil War . The command marched over 900 miles from California through Arizona and New Mexico Territory to the Rio Grande and as far east as El Paso , Texas , between April and August 1862 . Formation . The " California Column " originally consisted of ten companies of the 1st California Infantry , all five companies of the 1st Regiment California Volunteer Cavalry , Company B , 2nd Regiment California Volunteer Cavalry and Light Battery A of the Third U . S . Artillery . This command contained 1500 well drilled and disciplined men . Later on , Lieutenant Colonel George W . Bowie ' s 5th California Infantry was added , bringing the total strength of the Column to 2350 men . Expedition . The objective of their commander , Colonel James Henry Carleton ( promoted to brigadier general while the column was en route ) was to drive Confederate troops out of New Mexico , which they had occupied the previous year . The soldiers of the California Column , both infantry and cavalry , often traveled by foot wearing woolen uniforms in the desert heat . They started out from Fort Yuma along the Colorado River . Much like the Confederate Army of New Mexico ( also known as the Sibley Brigade ) , which had entered New Mexico from Texas in December 1861 , they traveled in small groups at intervals of a few days so men and horses would not exhaust the springs and wells along the way . They followed the established route of the Butterfield Overland Mail , which had ceased operation the year before . The mail posts were filled with food and grain which Union spies had stockpiled there before the invasion . Arizona battles . Arizona Confederate volunteers , the Company A , Arizona Rangers , arrested the Union Army agent , Ammi White , destroyed White ' s flour mill at Casa Blanca and supplies of food and fodder being gathered there and at other stage stations along the Column ' s route between Fort Yuma and Tucson . This slowed Carlton ' s progress . Most of Carleton ' s attempts to send messages to General E . R . S . Canby , the Union ' s departmental commander of New Mexico , were intercepted , and one patrol sent to meet White was captured by Confederates at White ' s Mill at the Pima Indian villages . During their advance the California Column engaged the Confederates in two small skirmishes . The first a skirmish with Confederates attemping to burn forage gathered at Stanwix Station near the end of March 1862 . The second clash came in mid - April when the column marched on Tucson from Casa Blanca , at Picacho Pass . Their subsequent rapid approach to Tucson nearly trapped the Confederate rearguard . After the fall of Tucson , pioneer Sylvester Mowry was arrested at his mine in Mowry , Arizona by the Californians . General Carleton , an old enemy of Mowry , charged him with selling lead for musket balls to Confederates . Mowry was imprisoned for six months at Fort Yuma before being released due to the lack of evidence , and as a result his mine was destroyed and he was forced to leave Arizona where he had intended to settle . It was not until late June that a scout named John W . Jones was able to outrun pursuing Apaches and get a message to Canby : " The Column from California is really coming . " On the march to the Rio Grande , 140 men of Company E , 1st California Infantry , and Company B , 2nd California Infantry , fought the famous Apache leader Cochise at Apache Pass in July . By the time the California Column reached the Rio Grande , the Confederates had already retreated to Texas . Carlton followed them into West Texas , capturing Franklin , Texas and advancing as far as Fort Quitman . Most of their service after that would be as garrisons in West Texas to prevent the return of the rebels . Their main activity was as garrisons of the settlements and forts in New Mexico Territory , and in fighting against the Apaches and Navajo .