Jefferson was first named Conser's Ferry, after the 1848 pioneer settler, Jacob Conser. Conser built his ferry in 1851. Jefferson Institute, named for Thomas Jefferson, was established in the vicinity of the ferry and the name was eventually adopted by the community. It is, even today, a farming community.
Mike Barnes at mikieb@quik.com was kind enough to contribute a couple of pictures of early Jefferson from his collection.