The Koeppens from Brandenburg Prussia came in at least 2 waves to Dodge County Wisconsin before moving to Shawano County. The family of Johann Köppen, wife Fredericka and at least one son, Carl August, supposedly arrived in 1853.
From History of Northern Wisconsin - Shawano County, 1881.
"AUGUST KOEPPEN, Treasurer of Shawano County, Shawano, was born and reared in Germany, and came to Dodge Co., Wis., in 1853, and took up the vocation of farming, but subsequently left it and traveled through the Southern States. In 1861, he enlisted in Co. D, 4th Wis. C., and after an active service, during which he was wounded, he was honorably discharged in 1862. After his services in the war, he turned his attention again to the agricultural industry, and came to Shawano, where he has been prominently identified since. In 1870, he was elected Circuit Court Clerk of his county for 1871-2. In 1879, he was elected County Treasurer and has been continued in office since. He has held a membership on the County Board from 1870 to 1878. In 1862, he was married to Miss Caroline Frailing, who was born in Germany and reared in Wisconsin. They have a family of two sons, Charles Emil and Herman August. Mr. Koeppen is one of the active, enterprising men of Shawano County."
So far I do not find any record of them in Dodge County, no 1860 census (?) but in 1857 Christian Koeppen from Uckermark, Templin, Brandenburg, Prussia came to Dodge & appears on 1860 Census, they could be closely related, as I find it interesting that Christian also moved to Shawano County after Carl August.
Another son of Johann, Friedrich Wilhelm, came direct to Shawano in 1880 and is buried in the same churchyard with his parents. He claimed to have been born in Alt Güstebiese, Preußen & his father supposedly lived in Neu Güstebiese before immigrating in 1853.
Another mystery is the identity of Charles "Karl" Ludwig "Lewis" Koeppen who married the widowed mother-in-law of Carl August Koeppen in 1852 in Dodge County. Sophia, nee Kraut, Froeling (Frailing etc)
"Sophia Fraleah Marriage Date: 28 Dec 1852 County: Dodge Volume: 04 Page: 0022 to Charles Lewis Koppen.
In 1860 Dodge County he's listed as "Charles Keppin", not sure what became of him but in 1880 she's living with son-in-law August Koeppen in Shawano County listed as "divorced". But some may have confused this man with her last husband on later records?
Her daughter Caroline married August in Dane County Wisc. after he was wounded in the Civil War, but Koppen is written Weppen.
Wisconsin, Marriages, 1836-1930.
"Groom's Name: Augustus Weppen (sic) Groom's Birthplace: Prussia. Bride's Name: Caroline Frolick. Marriage Date: 25 Dec 1862 Marriage Place: Madison, Dane, Wisconsin Groom's Father's Name: John Weppen Groom's Mother's Name: A. Weppen Bride's Father's Name: Christie Frolick"
This caused much confusion when she applied for widow's pension later on!
well I hope to hear from anyone with pieces to this puzzle...