Sterling Price

Major-General Sterling Price (September 14, 1809 – September 29, 1867) was a United States General and senior officer of the Confederate States Army who fought in both the Western and Trans-Mississippi theaters of the American Civil War. He rose to prominence during the Mexican–American War and served as governor of Missouri from 1853 to 1857. He is remembered today for his service in Arkansas (1862–1865) and for his defeat at the Battle of Westport on October 23, 1864.
Price was initially a strong supporter of the Union. He backed Stephen A. Douglas for president in 1860. When the states of the Deep South seceded and formed the Confederate States of America, Price opposed secession by Missouri. He was elected presiding officer of the Missouri State Convention on February 28, 1861, which voted against the state leaving the Union. The situation changed markedly, however, when pro-Union Francis Preston Blair, Jr. and Capt. Nathaniel Lyon seized the state militia's Camp Jackson at St. Louis. Outraged by this virtual declaration of war against the state, Price gave his support to the secessionists.
Pro-Confederate Governor Claiborne Fox Jackson appointed him to command the newly reformed Missouri State Guard in May 1861, and Price led his recruits (who nicknamed him "Old Pap") in a campaign to expel Lyon's troops. By then Lyon had seized the state capital and pushed through a bill to remove Governor Jackson from office and replace him with an unelected Union governor. The climax of the conflict was the Battle of Wilson's Creek, fought on August 10, where Price's Missouri State Guard, supported by Confederate troops led by Brigadier General Benjamin McCulloch, soundly defeated Lyon's Army of the West
Price was not finished as a Confederate commander, however. He contested Union control over Arkansas in the summer of 1863, and while he won some of his engagements, he was not able to dislodge Northern forces from the state, abandoning Little Rock for southern Arkansas.
While devoted to the Southern cause, Price's goals in his Confederate military operations were directed to liberating his home state of Missouri. Although he achieved victories during all phases of the war, his strategically most important battles (other than Wilson's Creek) all ended in defeat.
Rather than surrender, Price emigrated to Mexico, where he and several of his former compatriots attempted to start a colony of Southerners. He settled in a Confederate exile colony in Carlota, Veracruz. There Price unsuccessfully sought service with the Emperor Maximilian. When the colony failed, he returned to Missouri.
https://en.wikipedia.org/wiki/Sterling_Price