Constitutional Convention

Delegates arrived in Philadelphia in May 1787 because the Articles of Confederation had proved unworkable. The national government could not tax, could not regulate interstate or foreign commerce, and could not compel states to comply with its decisions. Shays' Rebellion in Massachusetts the previous winter had shown it could not even raise a force to put down domestic unrest. Fifty-five delegates from twelve states attended; Rhode Island sent none. George Washington presided, and the delegates met in secret.

The convention's central disputes were over representation and slavery. The Virginia Plan proposed a strong national government with a bicameral legislature in which both chambers were apportioned by population, favoring large states. The New Jersey Plan countered with a single chamber giving each state an equal vote. The Great Compromise, sometimes called the Connecticut Compromise, resolved the deadlock by creating a House apportioned by population and a Senate with two seats per state. The Three-Fifths Compromise counted three-fifths of the enslaved population toward a state's representation and direct taxation, and delegates further agreed to bar Congress from prohibiting the international slave trade for twenty years.

The finished document was signed on September 17, 1787, and sent to the states for ratification by special conventions rather than by existing legislatures. Supporters, calling themselves Federalists, argued for it in essays later collected as The Federalist Papers, while Anti-Federalists objected that the new government was too powerful and lacked protection for individual rights. The Constitution took effect after the ninth state ratified in 1788, and the promise of a bill of rights — added in 1791 — was decisive in winning over several holdout states.

AP U.S. History treats the convention as a pivotal moment in the 1754 to 1800 period, testing the plans, compromises, and the ratification debate. AP U.S. Government approaches it as the foundation of American constitutional design, focusing on why the framers chose separation of powers, federalism, and checks and balances over the confederation model.