I have recently compiled the following information about the oldest ancestors of all descendants of any Schwenningen JAUCH. I want to thank Axel Bauder, Peter Schifferdecker and Kristen Ahlstrom for sharing their own excellent research that contributed to this compilation.
Links to the GEDCOM details for each of the individuals below (including sources making the case for this pedigree) can be found on the website version of this narrative athttp://freepages.genealogy.rootsweb.com/~jillaine/jauch/Earl...
JAUCH Forefathers & Mothers
My current theory, supported by a fair amount of evidence, is that the oldest known JAUCH ancestor and forefather of all Schwenningen-based JAUCHs is Mathaeus-Theis JAUCH, b. abt. 1500, possibly in Schwenningen or one of the nearby towns. (Generation numbers are included in parentheses with each name.)
In 1535, he and his brother, Mathis-This JAUCH (yes, I realize the similarity in names is confusing) were given to manage a "Fronhof" (also called "Blaisihof" and later the "Unruh-Hof") in Schwenningen by the Catholic monastery of St. Blaisen. This was a feudal relationship that required the recipients (vassals) to compensate the monastery with tribute from the proceeds produced by the land.
The brother Mathis appears to have died by 1545 (after which time there is no mention of him in any records). We have no evidence that he married or had offspring. (1) Mathaeus-Theis JAUCH, however, was married twice, and had at least one son by the first and three sons by the second wife. This second wife, whose name goes unrecorded, was our "foremother." She died in 1576. (If there were daughters, their names weren't recorded.)
One of Mathaeus-Theis's sons by his second marriage was (2) Gorgus JAUCH, b. abt. 1540 and last recorded in Schwenningen in 1610. He shared the "Blaisihof" property with his only surviving brother. He also married and had at least two sons (again, the wife's name is not mentioned; nor are any names of daughters).
One of Gorgus' sons, Georg JAUCH (~1585-bef. 1649) is a forefather of the GERSTER line (his daughter Agnes married Martin GERSTER). We have no record of other JAUCHs from this Georg's line. Another son of Gorgus JAUCHs was (3) Hanss JAUCH (~1585-~1649). As in the previous generations, these two brothers shared the St. Blaisihof property.
Then came the Thirty Years War (1618-1648), and the town of Schwenningen was destroyed in February 1631. The two brothers (Georg and Hanss) did not survive the war, and if they had any sons, they also apparently did not survive the war.
One of Hanss' daughters, however, did survive. Her name was (4) Catharina JAUCH (~1611-1663). Her inheritance, unfortunately, included a significant debt left by her father and uncle-- a debt the St. Blaisen Monastery would not forgive despite the tragedy of the war. (The Catholic monastery probably would not forgive these debts because Schwenningen was so heavily Protestant.)
The "Blaisihof" was put up for auction. A JAUCH relative (how he was related is not known) came to the rescue. (4) Michael JAUCH (~1621-1693) not only purchased a piece of the property; he also married his "cousin" (by how many times removed we do not know), Catharina.
Michael Jauch was the son of (3) Veith JAUCH (~1594-~1657). Veith apparently had property from St. Georges Monastery, which he apparently sold to his son Christian. Peter Schifferdecker believes Veith was married twice; we know that one of the wives was Ursula (~1597-bef. 1660). Veith had at least eight children. We do not know if Ursula was mother of them all. For now, we record her as our "foremother" on this second JAUCH branch. We do not have any additional information about Veith's or Ursula's parents; we only know that Veith was somehow related to the brothers who managed the St. Blaisen property. He is therefore likely a descendant or cousin of (1) Mathaeus-Theis JAUCH, but we cannot confirm this yet.
In either case, the (1) Mathaeus-Theis JAUCH branch and the (3) Veith JAUCH branch continued to intertwine in future generations, as did most branches of any Schwenningen-based surname. As far as I can tell, ALL subsequent JAUCHs who can be traced to Schwenningen, are descended from (3) Veith JAUCH and/or (1) Mathaeus-Theis JAUCH.
Please let me know if you have any questions, or if you disagree with any of this. I am happy to discuss different theories.