Peter Mitchell Jr. was the son of the Rev. Peter Mitchell (or Mishler), who lived on the South Fork in Pendleton County. He was the pastor of the Lutheran church there on the South Fork, and owned considerable land. He died sometime after 1809, as we have a deed from him, dated Sept. 5, 1809, to his son George "Mitchler," for 30 pounds, of 2 tracts containing in all 128 acres on the South Fork, next land of Henry Swatley and Frederick Propst. (Pendleton County Deed book 5, page 126).
Another signature of Rev. Peter Mitchler - to receipt, dated March 28, 1801, for 12 sh. subscribed to the minister - in the estate papers of John Snider.
Soon after their marriage, Peter Mitchell Jr. and his wife evidently removed from Pendleton County to make a new home for themselves elsewhere. At first they seem to have lived in Randolph County as of date Aug. 28, 1794 we have Peter Mitchell and wife Hannah of Randolph County making a deed to Jacob Teter also of Randolph, for 45 pounds, of land on the south side of Leading Creek, a branch of the Tygarts Valley river, adjoining the land of Jonathan Buffington. (Randolph County, Deed book #1, page 419; also recorded in Minute book of the Randolph Court, book #1, page 282).
About 1797, however, they evidently decided to go farther west, for Peter Mitchell Jr. is said to have been in Rev. David Badgley's party who came to Illinois in 1797, and we find Peter and Hannah Mitchell living in St. Clair County, together with Abraham Teter and Mrs. Barbara Shook, in 1804 and later.
Peter Mitchell voted in Cahokia, Illinois. in 1799 (History of St. Clair County published by Brink, McDonough & County, page 70), and in 1804 Peter Mitchell was making improvements south of Silver Creek in that county (same, page 53). He is there also said to have been a respected citizen, a Justice of the Peace and County Commissioner. A son, Isaac, born in 1805, is said to have been the first male child born in Fayette precinct, and a child of Peter Mitchell who died in 1806 (whether this same Isaac or not is not known) was the first death in the community. Peter Mitchell, as Justic of the Peace, married many of the younger couples there. In the organization of the Silver Creek Baptist church in 1811, Peter Mitchell and Hannah Mitchell were among the constituent members. (same, page 166)
Peter Mitchell, after the death of his wife Hannah (Teter), married in St. Clair County Illinois, on April 25, 1820, Mary (Kittle) Teter, the widow of Hannah's brother, Abraham Teter.
Peter Mitchell Jr (Mischler) 
