The Roehrig families I am researching came from what is now known as RhinlandPfalz but before 1870 was part of Bavaria and was known as the Bavarian Pfalz. They came from the towns of Kapsweyer and Steinfeld which are located a few miles from the French border in the Roman Catholic Diocese of Wiesembourg, which I believe in in France. Other towns in which I have found Roehrigs or related surnames are Landau, Niederotterbach, Lauterburg, Schleithal, Schweighofen, Schweig, Altenstadt-Elsass, Hageneau-France, Herxheim, Oberlauterbach, Schaid all in the same vicinity. There are three known Roehrig lines in the US that originated in Kapsweyer/Steinfeld - one in St. Louis, one in Kingston, NY and one in Newburgh, NY. They are related.
Thought it would be interesting to try to connect other Roehrig lines. Please contact me if interested.