Cowgill, devoted abolitionist and a Quaker, freed his family's slaves and allowed them to meet in the great hall at Woodburn.

In his ownership the brick front porch, pillars on the south facade, a reflecting pool and numerous interior modifications were completed.

The Governor's House holds great architectural significance as an exemplary surviving specimen of high-quality 18th century residences in Delaware.

It has been diligently preserved as an essential component of the State museum system, which aims to showcase representative Delaware houses from different eras and socioeconomic strata.

Charles Hillyard (1759-1814), the builder of this historic structure, belonged to the fourth generation of a prosperous landowning family that actively participated in the government, social, and economic affairs of Kent County, Delaware.

Supported by local tradition, geographical circumstances, and the owner's known abolitionist views, this house is believed to have served as a stop on the renowned "underground railroad."

In George Alfred Townsend's novel, The Entailed Hat (published in 1884), it is depicted as the site of an attempted abduction by Patty Cannon's gang.

Additionally, this historic dwelling once served as the residence of Mrs. Vera Davis, Delaware's pioneering female legislator.