[30][39]

Indiana territorial governor
See also: History of slavery in Indiana and Indiana Territory
Harrison began his duties on January 10, 1801, at Vincennes, the capital of the Indiana Territory.[40] Presidents Thomas Jefferson and James Madison were both members of the Democratic-Republican Party, and they reappointed him as governor in 1803, 1806, and 1809.[30] In 1804, Harrison was assigned to administer the civilian government of the District of Louisiana. He conducted the district's affairs for five weeks until the Louisiana Territory was formally established on July 4, 1805, and Brigadier General James Wilkinson assumed the duties of governor.[41]
In 1805, Harrison built a plantation-style home near Vincennes that he named Grouseland, in tribute to the birds on the property.[19] The 26-room home was one of the first brick structures in the territory;[42] and it served as a center of social and political life in the territory during his tenure as governor.[43] Harrison founded a university at Vincennes in 1801, which was incorporated as Vincennes University on November 29, 1806.[44] The territorial capital was eventually moved to Corydon in 1813, and Harrison built a second home at nearby Harrison Valley.