An aunt of my father-in-law's married Joseph Hottman in Arena. I am wondering if this connects with your family. If so, I will contact her descendants--or perhaps you are already in touch with them?
Joseph Hottman, son of John G. and Mary (_____) Hottman married, at Black Earth, Wisconsin, June 26, 1901, Loveday Jane Ralph, daughter of John and Rose Annie (Ray) Ralph. Joe was born in Arena, Wisconsin, March 31, 1871, and died in Mazomanie, Wisconsin, September 25, 1951. Loveday was born at Shullsburg, Wisconsin, September 12, 1882, and died at the home of her daughter Babe Cowling, in Cross Plains, Wisconsin, November 22, 1959. Loveday and Joseph Hottman are buried in Arena.
children of Loveday Jane Ralph and Joseph Hottman:
i. Elsie Marie Hottman was born in Arena, June 21, 1902, and died in Elgin, Illinois, February 20, 1981. She married, in Mazomanie, Melvin Westland.
ii. Gladys Jane Hottman was born in Dover, Wisconsin, June 3, 1906, and died in Cross Plains, in March 1981. She married, in Madison, Ralph Lloyd, son of Evan and Mary Jane (Curtin) Lloyd. Ralph Lloyd was born in Arena, December 11, 1898, and died in Madison, February 14, 1973. They are buried in Cross Plains. They lived in Madison in 1959.
iii. Margaret Ann Hottman was born in Dover, March 6, 1908. She married, in Mazomanie, February 14, 1942, James Lloyd, son of Evan and Mary Jane (Curtin) Lloyd, and brother of Ralph Lloyd, who married her sister Gladys. He was born in Arena, March 10, 1897, and died in Prairie du Sac, Wisconsin, June 9, 1980. They lived in Arena.
iv. John Bernhardt Hottman was born in Dover, February 13, 1913, and died in Madison, March 11, 1967. He married Janette Harrop.
v. Martha Gertrude "Babe" Hottman was born in Dover, September 24, 1916. She married Milford Keith Cowling.
If you think this connects with your family, I will let Loveday's and Joe's descendants know. I think they would be thrilled to learn of your research about ancestors in Germany.