Hello Michele,
you won't find your Gahr ancestors in the Miltenberg microfilms. Bürgstadt
has always been a parish of its own. All baptisms, marriages and funerals in
Bürgstadt are listed in the familybook "Bürgstadter Familienbuch" which is
available in the Rathaus (mayors office) there.
The book contains several Gahr entries.
If your family came to the US in 1871 it was probably the following family:
Leonhard Gahr (born Sep. 3rd, 1820) married Oct. 26th, 1847 to Maria
Elisabeth Helmstetter (born August 21st, 1817).
They had 5 children: Franz (born and died in 1850), Barbara, born Sep. 8th,
1854, Theodor (born and died in 1857), Theresia, born Jan. 17th, 1859 and
Karl (born and died in 1862).
The book does not mention more about this couple and its kids, so it is
likely that they went to America. However, there is another related Gahr family
listed where the book clearly states they went to Newark. Ludwig Gahr, nephew
of Leonard (born 1851) was married in Newark in 1911 to the widow Eva Walter,
né Tittel. His sister Mathilde went also to the US.
Leonhard Gahr's parents were Leonhard Gahr (born 6.Nov.1768 in Gonsenheim
near Mainz) and Maria Anna Seibert, born app. 1778 in Hambrunn. She was daughter
of Georg Seibert and Anna Gauckel and died 29. June 1863 in Bürgstadt.
Leonhard Gahr died 13. June 1847 in Bürgstadt.
Please provide me with more details of this family just to ensure it is the
right one. I can send you then more details.
Best regards
Thomas