I am the person that supplied Terry with the information about Matthias Achenbach.
This is what we know and how:
1. Terry and I are both descended from Anthony (aka. Anton or Antonius) Achenbach.This is readily traceable through the church and civil records of Lancaster, Berks and Schuylkill Counties in PA.
2. Anthony's death record, from St. John's Union Church in Friedensburg, PA, lists his birth date as 15 Sep 1749 in Dorf Eisen, Germany.This information comes from a typed transcript of the church records.I have not seen the original and can not be sure how good the transcription is.
3. We have tried to figure out what town might be with no success.We have searched the church records from a number of towns with names that are similar to this in the Nassau-Siegen region and the surrounding areas.
4. From the probate records we are fairly certain that Anthony was the son of Johann Matthias Achenbach (also written Achebach).Matthias lived in the northeast corner of Lancaster County.His estate was probated 23 Feb 1794.Matthias's wife was named Anna Margaretha.
5. We are confident that he was the same person as Mathias Achebach who arrived in Philadelphia on the ship Friendship and signed the oath of allegiance on 21 Oct 1754.
I don't know if that will help connect with any information that you might have.It has been a sore spot that I was unable to resolve Matthias's and Anthony's place of origin.