I believe the unit he is alleged to have served in was the pre-war/very early war Missouri State Militia (not to be confused with the later Unionist MSM). The pre-war MSM was controlled by southern-supporting Governor Claiborne Jackson. Service in the organization was mandatory (although widely disregarded by Unionists), much as service in the war-time Unionist Enrolled Missouri Militia was mandatory. The indication is that Johnston served in the Ralls County Missouri State Militia, possibly in early to mid-1861. I have no reason to disbelieve the allegation, although I have never delved into pre-war MSM muster lists, or know if they even exist. The Missouri State Archives online listings seem to generally apply to wartime service, and not to service in peace time.

In any event, while Johnston's politics did evolve--and evolve drastically--I doubt he was ever secession-supporting. He was born in Pennsylvania on 6 Oct. 1834. Around 1845 the family moved to a farm near Sidney (now Shiel) in Ralls County, Missouri. He was a teetotaler, a teacher--including a stint in Pike County--and an occasional preacher.

He was a Conservative in the early days of the war. Starting in September 1861 he served as a private in Fagg’s Six Month Militia, which was raised in Pike County. In this unit were individuals who would go on to be major powers in the Missouri Radical hierarchy--TJC Fagg, George W. Anderson and D.P. Dyer--and who likely guided Johnston’s later career trajectory.

In July 1862 Johnston was a captain in the 53rd EMM. Promoted to major in October. In December of that year he obtained a controversial order relieving all other men in the regiment of duty, excepting himself and 60 picked men. During that same time he began being hammered in the Radical press. At least two officers, one in the 53rd EMM and one in the 3rd MSM (who was serving as Ralls County provost marshal) made sworn statements to a state legislative investigating committee alleging Johnston’s service in the pro-Southern pre-war militia.

Shortly afterward Johnston made the conversion to Radical. He was detailed to the 2nd PEMM in the spring of 1863. Resigned his commission in the course of the Radical purge of PEMM officers that fall. Afterward served as an officer in the Pike County Radical political organization. Served as major in the 39th Missouri Infantry in Sept. 1864. Killed, allegedly by Jesse James, at the Battle of Centralia on 27 Sept. 1864.

The very first Federals to rush to the scene were Pike County Radicals--Col. D.P. Dyer, who hopped a train out of St. Charles, and stopped off in Mexico Mo. to pick up two of his companies of the 49th Missouri Infantry. Dyer was the first to arrive at Centralia in the battle’s aftermath, and loaded up the in-town casualties onto the train and took them back to Mexico where he buried them in a mass grave; Lt. Col. Dan Draper (under whom Johnston had served in Fagg’s Militia), arrived with the 9th MSM Cavalry later that day and had the casualties in the countryside brought in and buried in a mass grave in Centralia. Draper released Johnston’s body to family members.

Johnston is buried at St. Jude’s Cemetery in Monroe City. The dead buried in the Centralia and Mexico mass graves were later reinterred in the National Cemetery in Jefferson City (despite a popular misconception, Johnston is not buried in the National Cemetery).