What was the plan for national government where states would keep their freedom and independence

Federal government is the name for this system of government. Under this system, states get to retain their individual rights and maintain their own governments, but some duties, like currency and defense, are delegated to the federal government, which is elected by all the states working together. The Articles of Confederation was the first document establishing a federal government, in 1781, but the federal government created by that document was far too weak. In 1789, a new, stronger federal government was created by the ratification of the U.S. Constitution.

Gave a little freedom to blacks