Some of the facts regarding my Bahr ancestors are close to your's.I have a ggggrandfather named Ernest F. Bahr born in Posen about 1818, married to Cathryn Last. (Maybe another marriage) No death data.
Their son Julius Henry Bahr was born 3/29/1844 at Posen.He married Henritte Siebenecher 11/4/1873.He died 5/22/1929 in New Salem ND
Family stories had that he was in the Prussian army and was expelled for dueling.
They had 17 children, one of them, Ada Bahr was my ggrandmother, she was born 1/29/1890 in Richardson NE, and died 3/10/1979 in Columbia MO.She married Gustave Sievert 2/24/1909