I found what looks to be the 1860 census record of Herman Kroeber (see attached). He is enumerated as Herman Krorver, a farm laborer, in Nunda Township in McHenry County, Illinois. Here's the entire family:
Herman, age 32, born Saxony
Fanny, age 26, born NY
Esther, age 5, born IL
Eugene, age 3, born IL
Flora, age 3/12, born IL
Because he was listed as being born in Saxony, it is unlikely that he was part Kröber family from Winningen, Germany, as I previously stated. He is more likely from the Kröber family originating from Altenburger Land whose name comes from a small village east of Altenburg, Thuringia, named Kröbern.
I don't believe Altenburg, Thuringia; Leipzig, Saxony; or other areas of the present-day state of Saxony were ever part of Prussia. However, present-day state of Saxony-Anhalt was part of Prussia, known as the Province of Saxony from 1816 to 1945.
Herman Kroeber could have been born just east of the city of Zeitz. There are several small farm villages where Kröber families lived in or lived near as farmers. Those included: Sprossen, Loitsch, Spora, Nißma (Nissma), Kayna, and Hohenkirchen.
He was also listed as born in 1828. Others have him listed as born in 1832. This could have been an assumption because Fanny was born in 1834.
I also found a Hermann Kroeber, age 21, who arrived in New York on the ship "Gaston" on 1 Oct 1849. This sounds reasonable since he married Fanny Barnes of Erie County, NY in about 1852. Here's the link to that record:
http://www.castlegarden.org/quick_search_detail.php?p_id=821...