I just stumbled upon this thread of Rathsams and wanted to add my two cents worth.
My great grandfather, Christian Rathsam, came to the US about the time of Bismarck's wars to unify Germany (1870-1880s). His sister also came to the US (she was called Aunt Boehnke--perhaps her married name) and settled in Indianapolis. I believe she was older than he and came earlier. My grandmother said she owned the Southern Hotel in Indianapolis. My great grandfather came from Treuchtlingen, a town in Franken, now northern Bavaria, which is about halfway between Munich and Nurnberg. The town is on the Altmuhl River. It's on a major railroad line and is a minor connection in the rail system, enough so that it was bombed during WWII. Some years ago, I looked up the Rathsam family through the Mormon geneology collections and found a record of a woman living in Treuchtlingen in the 1500s with the name of Rathsam. The name is unusual, but I suspect that it referred to someone who gave advice--an advisor to the local count. There is a castle at Treuchtlingen, which belonged to the Pappenheim family--their main roost was in Pappenheim, downstream from Treuchtlingen. The castle at Treuchtlingen was restored (from ruins) within the last 10 years or so and is now a lovely hotel. Much of the old town remains, and the community has made an effort to mark points of historical interest--such as the site of the synagogue, destroyed on Kristallnacht, and a Jewish school. There is also an old Jewish cemetery there.
The archeopteryx, a fossil indicating the transition from dinosaurs to bird-like animals, was found not too far from Treuchtlingen. The region was once an inland sea and is now noted for its high-grade limestone and marble deposits that are rich in museum-quality fossils. The outcroppings are still used to quarry stone, which is easily recognizable in buildings not only in the area, but throughout Germany. Lithography, which uses this stone, was developed in the Altmuhl region as well.
During my first visit to Treuchtlingen, in 1972, I tried to get access to records in the city hall--but was told that they were damaged during the war and were too fragile to be used. However, since technology has advanced, perhaps it's time to ask again.
I hope my rambling might be helpful or jog some memories for other Rathsams!