from Wikipedia Monaco:
Monaco, officially the Principality of Monaco (Monégasque: Principatu de Múnegu; Occitan: Principat de Mónegue; French: Principauté de Monaco) is a small sovereign city-state located in Western Europe. The territory lies on the northern coast of the Mediterranean Sea and is completely enclosed by France. Monaco is often regarded as a tax haven, and many of its inhabitants are wealthy and from foreign countries (including France), although they are not a majority.
Monaco is a Constitutional Monarchy and Principality with Prince Albert II as head of state. The Grimaldi family has ruled over Monaco since 1292 and the state's sovereignty was officially recognized by the Franco-Monegasque Treaty of 1861. Despite being independent, Monaco’s defense is still the responsibility of France.
Monaco is the world’s most densely populated sovereign country, and the world's smallest French-speaking country.