When Illinois was still a part of the American frontier, the Chicago Historical Society began collecting and preserving manuscripts and museum pieces important in the development of the great Northwest. It was in 1856 that a group of Chicago's foremost citizens, led by Dr. William Barry, founded the Society. A year later the organization was incorporated under the laws of the State of Illinois. According to the articles of incorporation, the purpose of the Society is “to institute and encourage historical inquiry and to collect and preserve the materials of history especially concerning the states carved from the Old Northwest Territory.” In this broad field, the activities of the institution have been chiefly of two sorts, the assembly of manuscripts and other material for its Library and the collection of historical pieces for its Museum.