Active in the Democratic Party, Yell moved to the Arkansas Territory in 1831 to head the federal land office in Little Rock. The federal government offered him the governorship of the Florida Territory the following year, but he declined. On March 21, 1832, Yell was appointed adjutant general of the Arkansas Territory with the rank of Colonel in place of Colonel Whorton Rector who had resigned. His time as adjutant general was apparently cut short by malaria." Yell left Arkansas for a time to recoup back home in Tennessee, but by 1835, returned to Arkansas, having been appointed as a Territorial judge. He was a strong supporter and personal friend of President James K. Polk. Just prior to taking office in 1845, Polk sent Yell to Texas to advocate for its annexation to the union. He is reported to have single-handedly retrieved a criminal from a local saloon and physically brought him to his court.