John Chamberlain has lived in the Minnesota River Valley for 60 years, having graduated from Le Sueur High School and returning after education to a career as a country banker in Le Sueur. He holds degrees from Macalester College and Cornell University and an Honorable Discharge from the U.S. Army.

Upon selling the bank in 1995, he retired to a second career of non-profit volunteer work in governance and fundraising for Macalester; Presbyterian Foundation; Minnesota Historical Society; Le Sueur County Historical Society; The Nature Conservancy–Minnesota/Dakotas Chapter, Trustee; Minnesota Valley Memorial Hospital & Foundation, Director and Trustee; Indianhead Council, B.S.A., St. Paul, Director; Le Sueur- Henderson Public School District 2397, director; Scoutmaster, Troop 328–B.S.A.; Rotary Club of Le Sueur, President; and many others.

He and his wife Katha have been married 52 years, have two grown sons, and live in Saint Peter after 40 years on a hobby farm across the River (looking at Nicollet County) in a stone house and stone barn, both on the National Register of Historic Places.