The following is not directly related to the above fascinating topic, but it may be close enough for government work, as it involves POW's, Shiloh and its aftermath.. John King was born in Randolph MA in 1816, graduated from Harvard in 1839, then studied law in the Boston office of the immortal Rufus Choate. He was a lawyer in Elgin, Illinois by the mid 1850's. In 1861, well into his 40's, he attempted to raise a 90 day independent Cavalry Unit in Geneva, Illinois. He was progressing well and had obtained 0.69 cal percussion cap muskets after communicating with General R.K. Smith in Chicago. A rival Elgin attorney, E. Joslyn , with a mob comprised of members of the Elgin Continentals (drilled by the immortal Ellsworth) stole by force the muskets from the jury room at the Kane County Court House in Geneva. Members of both groups were injured. The "collision" was noticed locally but quickly all but forgotten.
When John King left Geneva he had three young children named John Reginal, Lincoln, and Geneva. John King was mustered into William Ford’s Independent Cavalry Company at Ottawa as a 2nd Lieutenant on 2 January 1862. This Company was attached to the 53rd Illinois Volunteer Infantry and assigned to District of Columbia, KY, south of Louisville. Before that King had seen action with Fremont's Body Guard in Missouri. By the time of the Battle of Shiloh Ford's Cavalry had been incorporated into the 15th Il Cav as Company L. This company became Halleck's escort and the company arrived at Shiloh with Halleck after the battle. After Halleck's departure for Washington, Company L became Grant's escort for a time.
Captains King and Elgin's Addison Keyes were part of a complicated campaign that began on 21 April 1863. The plan called for Col. Abel Streight and General Granville Dodge to move from central Tennessee into northwestern Alabama. Capt. King’s Cavalry company was with Col. Streight and Capt. Keye’s H Company of the 127th Illinois was with Gen. Dodge. Ford’s unit had been assigned to 15th Illinois Cavalry as Company "L" on December 25, 1862.
During 1862 Ford’s company had acted as General Halleck’s escort from St. Louis, Missouri, to Shiloh, Tennessee after the Battle there, and then to Corinth, Mississippi. It was then assigned as an escort to Gen. Grant. Private Painter was detailed as courier and perform this duty well until captured. Private Uriah Painter was “joined in” to Ford’s Company via the same path as Lt. King.
Painter’s biography includes the fact that he was captured in a skirmish at Bear Creek, Alabama, and was taken to several southern prisons and finally transferred to Libby prison. Being a strong healthy man when he was captured he weighed only 80 pounds when exchanged and passed through the lines at city point. He immediately joined his company and was in every battle in skirmish with them until he was captured again in 1864.
The engagement at Bear Creek, Alabama, involved Roddey’s Regiment, CSA, of Nathan Bedford Forrest’s Cavalry and elements of Granville Dodge’s force, USA, 23 April 1863 near Tuscumbia, AL. This action occurred before Streight’s force was detached to make a raid on Rome, Ga.
Dodge’s force was to screen Streight’s raiding force and then make a diversionary attack on Tuscumbia, Alabama. Then Streight would be detached to take nearly 2,000 troopers across northern Alabama and into Georgia with Rome the object. At the same time a Union force about the same size as Streight’s was to raid deep into Mississippi.
Col. Benjamin Grierson with two Illinois calvary regiments and one from Iowa was to penetrate down the middle of Mississippi tearing up RR’s and and wrecking communications. Grierson, who had been kicked in the head by a horse as a child and disliked the beasts, was spectacularly successful. He arrived in Union occupied Baton Rouge on 2 May 1863 having suffered a total of 24 casualties. Grierson became nearly as revered in the north as Nathan Bedford Forrest was in the south.
Many moving parts existed in the Western Theatre as Grant maneuvered to take Vicksburg in the spring and early summer of 1863. In short, Grant “invented” the amphibious assault and blitzkrieg. Facing a numerically superior but divided Confederate force, Grant defeated it in two strokes. He floated his empty transports past the Vicksburg batteries and gathered them below that citadel. He crossed his army at Bruinsburg, abandoned his supply lines, and rapidly advanced on Jackson, Missisippi. There he defeated Confederate forces under General Joe Johnston. Then he turned back west moving on Vicksburg, tearing up the railroad from Jackson behind him as he went. Vicksburg fell on 4 July 1863. Lincoln sighed, “Thank God,” and declared “The Father of Waters again goes unvexed to the sea.” Cut in half, the Confederacy was doomed, though the war brutally continued until 9 April 1865 at Appomattox.
Captain King was captured sometime in 1863, probably when Streight surrendered. He and Streight ended up in Libby Prison. Streight took French leave from Libby via the famous tunnel, was hidden for a time by family friends in Richmond until the coast was clear and then walked to Union lines. Whether King took the tunnel also is not known but he did not escape Libby and was transferred to Andersonville in Nov. 1864. He arrived via steamer from Wilmington, N.C at Camp Parole in Annapolis in March 1865 per the NY Times.
John King ended up in Boone, Boone County Iowa, where he was the mayor in 1878 and was a long time Justice of the Peace. His nemesis, Ed Joslyn, was at Shiloh and emerged unscathed. He left the service shortly thereafter. His son's wrote a 2 Vol History of Kane County.
I have not been successful is identifying much more that a few clues to John King, such as his muster record and pension card, plus other census odds and ends. Ed Joslyn's brother was the editor of the Elgin Gazette at the time of the "War at Home". The Geneva newspaper of the time, The Kane County Advertiser, contained a spirited editorial and report of a meeting of outraged Genevans, but only two unrelated issues of that paper are known to exist.
 Military, Illinois., Naval Dept, J.N. Reece, and I.H. Elliott. Report of the Adjutant General of the State of Illinois. Phillips Bros., state printers, 1901. p518. https://books.google.com/books?id=sAQTAAAAYAAJ
 A record of King’s promotion to Captain has not been found. He was “out of sight and mind” as a POW for much of the War.
 History of LaSalle County, Vol I, p639.
 Laliki, Tom. Grierson's Raid: A Daring Cavalry Strike Through the Heart of the Confederacy. Farrar, Straus and Giroux, New York, 2004.