According to the Constitution of Norway, which was adopted on 17 May 1814 and inspired by the United States Declaration of Independence and French Revolution of 1776 and 1789, respectively, Norway is a unitary constitutional monarchy with a parliamentary system of government, wherein the King of Norway is the head of state and the prime minister is the head of government. Power is separated among the legislative, executive and judicial branches of government, as defined by the Constitution, which serves as the country's supreme legal document.