The Middletown Historical Society of Middletown Delaware was founded in 1985. The organization was born from the grassroots fight to save an historic structure called Greenlawn in Middletown, Delaware. Since its founding in 1985, the Society has hosted house tours as well as lectures on the history of Middletown. The Middletown Historical Society also hosts the annual Olde-Tyme Peach festival, a tradition started in 1993.
The Middletown Academy is home to the Historical Society. The Academy opened its doors in October of 1826 as a private academy. In 1840, the school had 33 pupils. It became part of the public school system in 1876.
It is now owned by the Town of Middletown and is shared by the Middletown Historical Society and Middletown Main Street, Inc.