A successor unit to the Fremont Rangers was Company A, 12th MSM Cavalry, which was later redesignated Company K, 3rd MSM Cavalry. Additional information on the Fremont Rangers is included in my story on the Battle at Jackson Fairground in the main body of Chapter One, and especially in Footnote 3 of Chapter One. The chapter can be found at http://www.civilwarstlouis.com/JacksonFairgrounds/Ch1.htm