The question is simple: with the exception of city-states (like the Vatican), does the United States possess the world's oldest living government? I ask because every nation I could think of has had at least one of the following since 1789 (the beginning of the current system of U.S. government): Revolution Transfer of power from a colonial empire Reorganization or reform Capitulation to a foreign power Such a government may be out there, I just can't think of what it may be if it does exist. The U.S. government has existed in the same form since 1789. It was challenged during the Civil War, but was maintained and restored. Amendments are changes to the U.S. government, but they are themselves a part of the system.