I am a decendent of the Matthias St John family. There is alot of info. available about him that I found from Walton NY where our line of St Johns started out before moving to Minnesota. Here is partial text with a link for you to use You will find Matthias listed in this area of the link too:
To get you started on your search. Go to the Delaware County New York website, dcnyhistory.org. Scroll down to "Books on line" to page 463-Lewis Seymour St. John. There are lots of them listed here. Also page 719, about the last one in the book-Lindley E. Hoyt. C.W. St. Johnis (Cook) St. John. and other of his family here.
You can reach me through this site if you have other questions. Jim Knudsen(St John) Brainerd, MN