<P> The old Northwest Territory originally included areas previously known as Ohio Country and Illinois Country . As Ohio prepared for statehood, the Indiana Territory was created, reducing the Northwest Territory to approximately the size of present - day Ohio plus the eastern half of the Lower Peninsula of Michigan and the eastern tip of the Upper Peninsula . </P> <P> Under the Northwest Ordinance, areas of the territory could be defined and admitted as states once their population reached 60,000 . Although Ohio's population numbered only 45,000 in December 1801, Congress determined that the population was growing rapidly and Ohio could begin the path to statehood . The assumption was that it would exceed 60,000 residents by the time it was admitted as a state . Furthermore, in regards to the Leni Lenape Native Americans living in the region, Congress decided that 10,000 acres on the Muskingum River in the present state of Ohio would "be set apart and the property thereof be vested in the Moravian Brethren...or a society of the said Brethren for civilizing the Indians and promoting Christianity". </P> <P> On February 19, 1803, U.S. President Thomas Jefferson signed an act of Congress that approved Ohio's boundaries and constitution . However, Congress had never passed a resolution formally admitting Ohio as the 17th state . The current custom of Congress declaring an official date of statehood did not begin until 1812, with Louisiana's admission as the 18th state . Although no formal resolution of admission was required, when the oversight was discovered in 1953, Ohio congressman George H. Bender introduced a bill in Congress to admit Ohio to the Union retroactive to March 1, 1803, the date on which the Ohio General Assembly first convened . At a special session at the old state capital in Chillicothe, the Ohio state legislature approved a new petition for statehood that was delivered to Washington, D.C. on horseback . On August 7, 1953 (the year of Ohio's 150th anniversary), President Eisenhower signed a congressional joint resolution that officially declared March 1, 1803, the date of Ohio's admittance into the Union . </P> <P> Ohio has had three capital cities: Chillicothe, Zanesville, and Columbus . Chillicothe was the capital from 1803 to 1810 . The capital was then moved to Zanesville for two years, as part of a state legislative compromise, in order to get a bill passed . The capital was then moved back to Chillicothe, which was the capital from 1812 to 1816 . Finally, the capital was moved to Columbus, in order to have it near the geographic center of the state, where it would be more accessible to most citizens . </P>

When did ohio become part of the united states