We may be researching the same Gahm family. I have Johannes Gahm b. 15 Dec 1766 Katzweller Rheinland Pfalz Germany The last child he had born in GermanyOne of this mans children settled in Jackson Co Ohio. His name was Johannes also Born 10March 1807 He married Elizabeth Beck. Jacob H Gahm is the first child born in the USA in 1837. They have two children born in Germany Johannes Jr Gahm b. 1829 and Phillip Gahm b. 1831 so they had to have came to the USA between 1831 and 1837. I have not been doing any research on the ship they sailed over on so maybe this time line will help. Also my gransmother who was a Gahm said that they came over and were in Pensylvania for a while according to her dad. That would be Johannes Jr's Son named John Edward Gahm.