One company of this regiment did not go on this celebrated expedition because it was engaged, under Captain Clifton Wharton, in escorting a company of traders on the Santa Fe Trail as far as the Spanish boundary. In the summer of 1836 three troops of the Dragoon regiment, with six companies of the Seventh Infantry, marched from Fort Gibson to Nachitoches to aid the Texans in resisting what was thought to be an impending attack by a large force of Mexicans. The peril did not materialize and the troops returned to Fort Gibson after an arduous campaign of several months involving a march of a month each way. During their absence, and due to an exaggerated alarm of war with Mexico; several hundred men in Arkansas were mustered in as volunteers and remained in camp at Fort Gibson for months. Again, in 1837, a company under Captain Eustace Trenor escorted Colonel A. P. Chouteau to his trading house near the present Purcell, Oklahoma, where he called the wild Indians to a conference in an effort to counteract the machinations of the emissaries from Mexico and Texas who were trying to enlist them in their respective controversies. And in 1839 a detachment of Dragoons commanded by Lieutenant James M. Bowman escorted the famous trading expedition headed by Dr. Josiah Gregg to the limits of the United States on the way to Santa Fe and Chihuahua. Captain Nathan Boone headed a command of Dragoons that left Fort Gibson May 14, 1843, and followed an interesting route over the Santa Fe Trail and through the country west of this post in order to afford protection to traders from Texas. The Dragoons continued to police the West until this service was interrupted by the Mexican War, in which it distinguished itself in several important battles.