The Westmoreland Historical Society (WHS) is the primary steward of the county’s rich historical and cultural heritage, preserving and interpreting more than two centuries of regional history that shaped Southwestern Pennsylvania and the early United States. Founded in 1889, WCS connects people to the past through museum collections, archival resources, educational programming, and public events that foster historical understanding, civic pride, and lifelong learning.

Central to this mission is Historic Hanna’s Town, a nationally significant Revolutionary-era site and the original county seat of Westmoreland County. Established in the 1770s, Hanna’s Town served as a political and legal center on the western frontier and was the only county seat burned during the American Revolution. Today, the site operates as an outdoor history museum featuring reconstructed log buildings, archaeological resources, and immersive educational programs.