The Oberlin Historical and Improvement Society (O.H.I.O.) was formed in 1964 when the Oberlin Village Improvement Society and the Oberlin Historical Society merged.

The Oberlin Village Improvement Society was founded in 1903 by Adelia A. Field Johnston (1837-1910) with support from Oberlin trustee Charles Martin Hall (1863-1914).  The object of this organization was "to improve the town and beautify it as a place of residence."  The society's first effort was to clean Plum Creek and its banks throughout the village.  Property was purchased with the intention of creating an Oberlin park system following Plum Creek from the Arboretum to the outskirts of town.  Houses on the organization's property were used as community centers for such organizations as the Oberlin Kindergarten Primary-Training School, the sewing school, and other youth clubs.  In 1915 the society, chaired by Helen White Martin (1864-1940), merged with three other local societies to form the Oberlin Federation for Village Improvement and Social Betterment.  The group continued to offer lectures and other programs, promoting numerous good causes, including creating parks and crusading against dandelion infestations.  This practical, less costly planning represented Oberlin's commitment to the "City Beautiful" movement at the turn-of-the-century.

The successful drive to preserve two of Oberlin's historical landmarks--the Little Red Schoolhouse and the James Monroe House--from demolition during the late 1950s led in 1960 to the formation of the Oberlin Historical Society, O.H.I.O.'s second predecessor organization.  Clifford Barden (1890-1961), a public-spirited citizen, led the private-sector effort to save these two structures from demolition.

O.H.I.O.'s incorporation statement advocated "procuring, maintaining and operating the historically significant sites, structures, artifacts, records, and reproductions, along with promoting the community center's charitable and literary activities...."  An 18-member board of trustees manages O.H.I.O.  Since its founding, O.H.I.O. has acquired two additional historical properties and has promoted local historical interests in a variety of ways.  Sites presently being administered include the Jewett House, the Burrell-King House, the Little Red Schoolhouse, the James Monroe House, and the Oberlin Community Center Building.  In 1965 O.H.I.O. issued its first publication, The Churchill's of Oberlin, a biographical study of an Oberlin family by Earnest Barrett Chamberlain (1883-1972).  This was followed in 1968 by The Music of Oberlin and Some Who Made It, also by Chamberlain, and three autobiographical works by Frank Van Cleef (1881-1984) in 1976. In 1988 O.H.I.O. widened its commitment by endowing the Frederick B. Artz Summer Travel Grants Program at the Oberlin College Archives and, in recent years, by providing financial backing to a number of public programs dealing with local history.