Saint Peter’s is Rome and  Rome is Saint Peter’s: the connection between the city and the most famous church in Italy is so deeply rooted we tend to forget that, technically, the basilica and its cupolone are not in Rome and not even in Italy, for that matter, because the Vatican is an independent entity. 

The small city-state was created, in the form we know today, in 1929  with the Lateran Treaty, but as Papal States (or Stato Pontificio, as we read on Italian history books), it made the history of the peninsula for over a millennium. With its 618 citizens and 0.44 square km extension, it is the smallest sovereign state in the world.