Casper Thenner was born in 1831 in Germany. He stood 5’4” with blue eyes, light hair and a light complexion and was a 30-year-old laborer possibly living in Shiawassee or Kent County when he enlisted in Company C on May 13, 1861. (Company C was made up largely of German and Dutch immigrants, many of whom lived on the west side of the Grand River in Grand Rapids. This company was the descendant of the old Grand Rapids Rifles, also known as the “German Rifles,” a prewar local militia company composed solely of German troopers.)
Casper was taken prisoner on July 1 or 2, 1862, at White Oak Swamp, Virginia, confined at Richmond, Virginia, and paroled in mid-September. He was returned to the regiment on either November 15 at Alexandria, Virginia, or December 20, 1862, at Camp Pitcher, Virginia.
He reenlisted on December 21, 1863, at Brandy Station, Virginia, crediting Grand Rapids’ 4th Ward, and was presumably absent on veteran’s furlough in January of 1864 and probably returned to the regiment on or about the first of February.
Thenner was transferred to Company I, 5th Michigan Infantry upon consolidation of the 3rd and 5th Michigan Regiments on June 10, 1864.
He was taken prisoner on December 6, 1864, at Jerusalem Plank road, near Petersburg, Virginia and was sent from Petersburg to Richmond on December 10, 1864. Casper was paroled at Cox’s Wharf, Virginia on February 5, 1865, and furloughed as a paroled prisoner of war.
Casper returned to Grand Rapids, where he was examined by Dr. Charles Hempel. Dr. Hempel certified on March 20, 1865, that Thenner was “suffering from chronic diarrhea and general debility and is not able to travel and I further certify that in my opinion he will not be fit for duty in less than twenty days.”
Casper died of chronic diarrhea on May 27, 1865, in Grand Rapids and "his funeral was attended and the remains followed to the grave by a company, under command of Captain [Theodore] Hetz, of heroes, once members of the old Third. According to a local newspaper he was buried in the “city cemetery”.
This much we know. What we don't know is exactly where he is buried.
According to the online resource Findagrave.com, Casper was buried in Oak Hill Cemetery (Hall and Eastern streets). Certainly a number of men who died during the war are interred in the Watson GAR Post lot in Oak Hill but there was never any mention of Casper in the earliest records (newspaper or burial) and it seems unlikely he was interred there. Plus, the Grand Rapids Eagle reported that a procession of his former comrades "followed" the coffin to the grave, which lends credence to the theory that he was buried in Fulton since it was located right at the edge of town (Oak Hill was then out in the country). Finally, Fulton was the "city cemetery" during the war.
Since Casper was German- or Dutch-born it is, of course, possible that he was buried on the west side of the city but, again there is no reason to presume that to true beyond the simple fact that many European immigrants lived on that side of the river. Anyway, quite a few Dutch immigrants who died in the mid-nineteenth century are in fact buried in Fulton Cemetery. (For example, Martiena Van der Stolpe died in 1864 and Pieter Van der Stolpe died in 1866 and both and are buried in division 9 of Fulton.)
So, assuming Casper was buried in Fulton, where is his grave?
One starting place would be at what is today the back side of the cemetery but during the war a burial place of distinction. A number of other Old 3rd men who died during the war are interred at the top of the hill, in division 7: Lieutenants Peter Weber, Charles Cary, and Peter Bogardus and Captain Samuel Judd, while Brigadier General Stephen Champlin is buried in his own section right next to division 7.
Along the same ridge is division 8 which then slops downward to division 9 and the western boundary of the cemetery. It is in division 9 that Margaret "Maggie" Ferguson was buried in 1861. She had sewn the regimental flag presented to the regiment by the ladies of the city shortly before the regiment left Grand Rapids on June 13, 1861. He grave remained unmarked until sometime after the war when the Old 3rd Association paid to have a marker erected on it.
While there is little evidence beyond "reasonable speculation" to assume he is buried in division 8 or 9, I believe that either would be, at this point, the "most likely" location. Barring the discovery of sexton's records dating back to the mid-1860s, we cannot confirm tCasper's burial location one way or the other.
So, the question remains: where is Casper Thenner?