A recent article in the April/June issue of the NGS (National Genealogical Society) Magazine discusses differences between the two main waves of German migration, including place of origin and religious affiliation.
The earlier immigrants (1700s) generally came from southwest Germany, were mainly Protestant, followed the Rhine to Rotterdam and landed in Philadelphia--later settling in Maryland, Virginia and the Carolinas. They also were seeking more land.
Those who came later (1800s) left from Bremerhaven or Hamburg, as they came from the central and northern regions of Germany. They arrived in New York or New Orleans migrating to the Midwest or Texas.
Remember that these are generalizations but might provide a clue to your German ancestral origins. We will add this article to our German resource binder in the fall.