Glendower, now known as Glendower Historic Mansion and Arboretum, is a historic Greek Revival style house located at 105 Cincinnati Avenue, U.S. Route 42, Cincinnati Avenue, in Lebanon, Ohio.

It was built in 1836 by Amos Bennett for John Milton Williams, a Lebanon merchant, and named for Owain Glyndŵr (often anglicised as "Owen Glendower").

It has been called "one of the finest examples of Residential Greek Revival architecture style in the Midwest.

On December 3, 2007, it was transferred to the Warren County Historical Society, which ran the site until August 2022 as a museum.

Media related to Glendower State Memorial at Wikimedia Commons This article about a property in Warren County, Ohio on the National Register of Historic Places is a stub.