Explain the major compromises of the 1787 Constitutional Convention -- the Great Compromise, the Three-Fifths Compromise, and the Electoral College -- and why each was necessary.
In May 1787, fifty-five delegates gathered in Philadelphia with instructions only to revise the Articles of Confederation. Within days, many had decided to scrap the Articles entirely and write a new framework of government instead. Two rival plans emerged immediately. The Virginia Plan, favored by large states, proposed a strong national government with a two-chamber (bicameral) legislature in which each state's representation would be based on its population, which naturally favored states like Virginia and Pennsylvania. The New Jersey Plan, favored by small states, proposed keeping a single-chamber (unicameral) legislature in which each state got one equal vote, protecting small states like Delaware and New Jersey from being outvoted by their larger neighbors. The convention deadlocked for weeks until Connecticut delegate Roger Sherman proposed what became known as the Great Compromise (or Connecticut Compromise): a bicameral Congress with a House of Representatives apportioned by state population, and a Senate in which every state, regardless of size, gets exactly two seats.
Representation in the new House of Representatives raised an even harder, and uglier, question: would enslaved people count toward a state's population? Delegates from Southern states, where slavery was widespread, wanted enslaved people counted for representation, which would give those states more seats in Congress, even though enslaved people had no rights and could not vote. Delegates from states with fewer enslaved people objected that counting them for representation while denying them any citizenship made no sense. The resulting Three-Fifths Compromise counted each enslaved person as three-fifths of a person for both representation and direct taxation -- a deeply unjust arithmetic that boosted the political power of slaveholding states in Congress and the Electoral College for decades, until the Fourteenth Amendment (1868) formally nullified the three-fifths clause after slavery ended. A related compromise barred Congress from banning the international slave trade before 1808. Delegates also compromised on how to choose the president, rejecting both direct popular election and selection by Congress in favor of a new institution, the Electoral College, in which each state would appoint electors, roughly proportional to its congressional representation, to formally select the president.
Mastery looks like: They can explain the Virginia and New Jersey Plans, describe how the Great Compromise combined them, and explain what the Three-Fifths Compromise did and why it was later nullified.
Common stumbles: Thinking the Great Compromise was simply "everyone agreed," rather than a specific structural trade (two different chambers with two different rules); softening or omitting what the Three-Fifths Compromise actually did.