In the 4th century A.D., the Roman emperor Constantine I gave the Latolan Palace to the Roman church, which was the beginning of Roman bishops owning property. After the fall of western Rome, the Pope actually took control of Rome. In 756, Pippin, King of the Frankish Kingdom, dedicated a large area of land in central Italy to the Pope, and the papal state was established. Later, the territory of the papal state continued to expand. 1798, Napoleon led the French army to occupy Rome, forcing Pope pope pius vi to give up the territory of the papal state, abolish the secular rule of the Pope and establish the Roman Republic. 1800, Pope pope pius vii rebuilt the papal state. But nine years later, Napoleon incorporated the papal state into the territory of France and abolished it. At the Vienna conference in 18 15, the papal state was restored.
Around the 4th-6th century AD, the Vatican became the official residence of Roman bishops. 13rd century, it was rebuilt and expanded. About the second half of the14th century, the Latola Palace, where the Pope once lived, was burned down. The Pope entered the Vatican and began to hold a meeting here to elect the Pope. From 65438 to 60' s, during the Italian unification movement, the territory of the papal state was annexed by the Kingdom of Italy. 1870, the Pope's jurisdiction is only the Vatican. 1929, the Pope signed the Treaty of Latoran with the then Italian ruler Mussolini. Since then, the Vatican has become an independent sovereign country with the Pope as the monarch and the integration of politics and religion, thus laying the great shape of the Vatican as a country today. The Vatican has set up some institutions in Rome that enjoy diplomatic immunity. After the Second World War, the Treaty of La Toland became a part of the Italian Constitution. The Vatican covers an area of only 0.44 square kilometers and has a population of about 1000 citizens.