According to the Durango Naturalization Records, Ludwig Schoser was seeking citizenship in the United States between 1904 and 1906. These records typically include information on the precise date of naturalization, the nation of origin and the number of years the person had resided in the United States. Unfortunately, this information is not available online so that one would have to consult the paper archives at the Fort Lewis College Foundation, Center of Southwest Studies in Durango to know what Ludwig's country of origin was and when he emigrated to the U.S..
What we do know about Ludwig from other sources is that he was married to Dora (Schirmer) and had four sons (John, Otto 'Barney', Leo and Frank Joseph) and two daughters (Mary and Emma). In fact, he is the progenitor of a substantial number of Schosers in the U.S. some of whom still live in the area of Durango, Colorado.
