The political document that outlined the division of powers among branches of government is the United States Constitution, ratified in 1788. The Constitution established a federal government with three distinct branches: the legislative, executive, and judicial. Each branch has its own powers and responsibilities to prevent any one branch from becoming too powerful, embodying the principle of separation of powers. This framework promotes checks and balances, ensuring that each branch can limit the powers of the others. The Constitution serves as the foundation for American democracy and governance.