Grouseland was constructed at great personal expense to Governor Harrison. The territory at dawn of the 19th Century, had no established roads, and Vincennes itself, at time of construction, had a population estimated at only 700. For such a project, everything had to be imported. Many of the items within, were brought from Europe. It is surmised by at least one biographer, that Harrison's motives in constructing such a Xanadu in the wilderness, included establishing all respect due him as governor, despite his relative youth at the time, (e.g. "that he was a man to be reckoned with"). Grouseland served Harrison's position, as well a marker for his place in American aristocracy--William Henry was the youngest son of Benjamin Harrison, V, a signer of The Declaration of Independence.
During Harrison's governorship of the Indiana Territory, Grouseland was the focal point of the social and official life of the territory. As the capital of the Northwest Territory, more territory was governed from Vincennes than any city outside Washington, D.C. Grouseland was home to Harrison until 1812. It remained in the Harrison family until the late 1840s.
The mansion includes the council chamber where Harrison met with representatives from various American Indian tribes. In 1805, Harrison negotiated the Treaty of Grouseland with a number of important Indian leaders, including Little Turtle and Buckongahelas. Harrison had two confrontations with the Shawnee leader Tecumseh at Grouseland in 1810 and 1811. (see Tecumseh's War). Harrison's thirteen treaties with Native American leaders resulted in millions of acres of land being acquired by the United States. Grouseland was built from local materials by skilled labor. The architect was William Lindsay.
Today, Grouseland is owned by the Daughters of the American Revolution who saved the building from destruction. It is overseen by the Grouseland Foundation, a volunteer board of directors composed of DAR and non-DAR members to manage the structure and programs. The main campus of Vincennes University is adjacent to the property, and other state historic buildings, such as the Territorial Capitol building, have been moved to the property.