A review of the census records 1870, 1880 and 1900 imply he was from Prussia, not Wurttemberg, so I doubt he's from Schwenningen (which was part of Wurttemberg, not Prussia).
From the 1900 census, we can tell that he married about 1858 while still in Germany (and his wife's maiden name is not common to Schwenningen or Wurttemberg); that he emigrated in 1864 and went directly to Waconia, Carver Co., MN or is at least in Minnesota by September of that year because his son was born in MN then; they're in Waconia by the 1870 census and appear to stay there.
Well, you can rule out Schwenningen and towns around there in the Wurttemberg area. I say this because there was a rather large contingent of Jaeckles (various spellings) who came from this region between 1846 and 1870.
Sorry I couldn't be of more help.