Wagner was born on October 19, 1809, in Meckenbeuren, in what is now the state of Baden-Württemberg in southern Germany.
At the time of his birth, this area was part of the Kingdom of Württemberg in the Confederation of the Rhine.
He settled first in Troy, New York, where he worked as a school teacher for several years.
He moved west to Mount Calvary, Wisconsin, in Fond du Lac County, in 1846.
He was elected to the Fond du Lac County board of supervisors in 1848,[2] and ran unsuccessfully for Wisconsin State Assembly in 1851.