Even though the Declaration of Independence was successful and was announced on July 4th 1776, Federalists and Anti-Federalists still fought over the separation of powers in the country. Anti-federalists wanted more power for the states and less for the central government, whereas federalists wanted a strong central government.
The first "constitution" of the US was written 1777, and it had a lot of problems. Many different groups fought over all the problems it had. It didn't give the central government many powers at all.
Many ideas were proposed to the country's leaders to help fix the articles. The Connecticut Compromise gave each state 2 votes in the senate. Slave states wanted more votes for their slaves, but northern states didn't want the south to have all the power, so they decided on the "Three-Fifths" clause, where each slave counted as 3/5 of a person. And the smaller states were upset that they didn't get enough votes, so they wanted
At the Constitutional Convention, delegates chosen by each state to represent them. gathered to fix the Articles. They argued over the rules of our sovereignty and right to govern ourselves.
The Virginia plan gave us our three branches of central government. The Legislative, which creates or makes laws and has the power to declare war. The Executive branch enforces laws. and the Judicial Branch which interprets those laws and decides if they follow the constitution.