On July 13, 1787, Congress approved the Northwest Ordinance. The Northwest Ordinance served as a bridge between the Declaration of Independence and the Articles of Confederation as well as between the Constitution and the Bill of Rights. It was the most significant legacy of the Confederation Congress. By providing a generous philosophical and practical structural framework for colonial territories to be governed and to evolve into full-fledged states, the Northwest Ordinance ensured that the United States would not encounter the same colonial problems as other empires. The ordinance stated that once each of the American colonies reached a certain level of population, they could enter the Union as an equal member state. This policy, which was used for the five states that were carved out of the territory northwest of the Ohio River, served as the blueprint for most of the other territorial possessions of the United States that elected statehood.