When Peter Theodor Hemann was born on 12 October 1863, in Johnsburg, McHenry, Illinois, United States, his father, Joseph Peter Huemann, was 33 and his mother, Christiana Zerwas, was 21. He married Elisabeth Steiger on 17 January 1888, in Stacyville, Mitchell, Iowa, United States. They were the parents of at least 3 sons and 7 daughters. He lived in Stacyville, Mitchell, Iowa, United States in 1910 and Mitchell, Mitchell, Iowa, United States in 1925. He died on 29 February 1956, in Mitchell, Iowa, United States, at the age of 92, and was buried in Meyer, Mitchell, Iowa, United States.