 The Sioux City Grain Exchange was established on October 14, 1907 as the Sioux City Board of Trade by Fred L. Eaton, Clarence A. Knapp, and Granville B. Healy with the purpose to "foster and promote trade and commerce in Sioux City and to establish and maintain commercial and financial exchanges".It was first headquartered in the Grain Exchange Building (formerly Garretson Hotel) at 507 5th Street, which was destroyed by a fire on May 24, 1914.A second headquarters, also called the Grain Exchange Building (Insurance Exchange today), was built in 1916 at 507 7th Street.