My great-great-grandfather emigrated from Hamburg, Germany, to Guaymas, Sonora, Mexico by way of South America in the mid-19th century. His name was Heinrich Zeisz, but Hispanicized/translated his given name from Heinrich to Enrique. At some point in time his Mexican-born daughter (my great-grandmother) Hispanicized her surname from Zeisz to Saenz. Although not always the case, it is a common practice for immigrants to translate/change their names to blend more easily into the society in which they make their new home. I have seen the surname "Zimmerman" in many Mexican records. The surname "Zasueta" is, I believe, Basque, not German. Google "German surnames in Jalisco, Mexico" and see what you find. Good luck.