The historical figure recognized for shaping modern democracy is Thomas Jefferson. Serving as the principal author of the Declaration of Independence, he articulated the principle that government derives its legitimacy from the consent of the governed. His ideas on liberty, equality, and self-governance have profoundly influenced democratic thought and institutions worldwide. Jefferson's vision of a participatory government laid the groundwork for the U.S. Constitution and the Bill of Rights, cementing his legacy as a pivotal figure in the establishment of democratic ideals.