Final answer:
James Madison, born in Virginia, is known as the 'Father of the Constitution,' and was a key figure in proposing the three-fifths compromise and authoring the Virginia Plan at the Philadelphia Constitutional Convention.
Step-by-step explanation:
The father of the Constitution, who proposed the three-fifths compromise and authored the Virginia Plan, was James Madison. Born in Virginia in 1751, James Madison played a pivotal role during the Philadelphia Constitutional Convention. He contributed significantly to the structure of the U.S. government by incorporating Montesquieu's separation of powers with a system of checks and balances, and his Virginia Plan suggested a bicameral legislative branch where representation was based on population.
Recognized for his willingness to compromise, Madison also supported the Three-Fifths Compromise, which allowed a count of three out of every five enslaved persons for federal taxation and representation in Congress.
Madison's influence extended beyond the convention, as he authored over a third of the Federalist Papers, helped frame the Bill of Rights, served as Secretary of State, and later became the fourth President of the United States.