Anna Sophia Peterson was born May 31, 1864 in Kalmars län, Småland, Sweden the only daughter of Peter Peterson and Emma Sophia Dolk. She spent her childhood in Linköping, Östergötland, Sweden.

Alfred came to the United States with his parents and siblings in May 1871, at the age of 8 years. He became a citizen on 13 May 1884. Anna arrived in the USA with her mother and step-father in 1880.

Alfred and Anna were married March 14, 1882 in Crawford County, Iowa. They had thirteen children.