Governor Arthur St. Clair arrived within the Northwest Territory at Marietta, Ohio to begin administration of civil duties within the territory. St. Clair formally established the territorial government on July 15, 1788. The settlement of Losantiville was renamed by St. Clair to “Cincinnati” in 1790 and he moved the administrative and military center of the territory to Fort Washington.
Fort Washington was in downtown Cincinnati, providing easy access to the Ohio River. The Fort was the major staging area for settlers, troops and supplies during the settlement of the Northwest Territory.
The first written criminal and civil laws of the Northwest Territory were established. Thirty-seven different laws were written with the understanding that the laws had to have been passed previously in one of the thirteen original states. A structured court system was established.
Many early trips west began in Marietta or Cincinnati. The first part of Indiana to be settled was in the south and southwest, along the rivers.
The settlement of Indiana happened primarily from the rivers. The south and southwestern parts of Indiana were divided into counties first. Fort Vincennes was established by the French between 1731-1732. The Fort was later was occupied by the British who called it Sackville before it became a possession of the U.S.
Vincennes was used to muster soldiers to fight in the Battle of Tippecanoe in 1811. The soldiers marched along the Wabash to near the confluence of the Tippecanoe and Wabash Rivers. The area is known today as Battle Ground, Indiana. It was there that General William Henry Harrison met the confederacy of tribes led by Tenskwatawa, “The Prophet” for battle. Tenskwatawa was the brother of the great Shawnee warrior, Tecumseh, who was not at the battle.
Vincennes was the first capital of Indiana Territory until it was moved to Corydon on May 1, 1813.