What two historical documents established the principles of popular sovereignty?

The two historical documents that established the principles of popular sovereignty are the Declaration of Independence (1776) and the U.S. Constitution (1787). The Declaration asserts that governments derive their just powers from the consent of the governed, emphasizing the idea that political authority rests with the people. The Constitution further enshrines this principle by establishing a representative democracy, where elected officials are accountable to the electorate, thus reinforcing the notion that ultimate power lies with the citizens.