So the Catholic Church has a new leader. And the Vatican has a new head of state. Two job descriptions, filled by just one single guy [1]: the Pope.
Until very recently, Jorge Mario Bergoglio's main concern was tending to the spiritual needs of the 2.5 million souls in his flock, the archdiocese of Buenos Aires. But since his election as pontiff by the College of his colleagues [2] on March 13, the Cardinal now is Pope Francis, and thrust upon him are huge spiritual duties, but also a tiny temporal one.
The new Pope is the numero uno of the Holy See. In its strictest sense, this spiritual jurisdiction only comprises the diocese of Rome. But Rome is where Saint Peter was martyred [3] - and in the Catholic tradition, this Apostle was the first Pope, the current Pope being his 265th successor in an unbroken (though often quite wobbly) line. Hence the primacy of the papacy over other bishops [4], and the conflation of the Holy See with the entire Catholic Church – or at least with the highest echelons of its Roman bureaucracy, also known as the Curia [5].
Under international law, the Holy See is considered a sovereign entity, as it has been since the Middle Ages, and as such maintains diplomatic relations with most other countries. It is a member of various international bodies[6], and has permanent observer status at the U.N. General Assembly. However, the Holy See should not be confused with Vatican City, independent only since the Lateran Treaty of 1929. The two entities issue distinct passports, and they have different official languages: Latin for the Holy See, Italian for Vatican City.
The Vatican's external borders – or are they?
The Lateran Treaty, concluded between Mussolini's fascist Italy and the Holy See, sealed the recognition by the Pope of Italy's authority over the former Papal States [7] and Rome itself, and by Italy of the independence of Vatican City. Thus was resolved the so-called 'Roman Question', which had arisen in 1861 when almost-unified Italy had declared Rome its capital, and escalated when the Italian state took Rome from the Pope by deadly force in 1870 [8].
Without the independence of Vatican City, the Holy See's sovereignty would be comparable to that of the Knights of Malta [9]: with plenty of ambassadors scattered the world over, the Order is considered sovereign – but lacking a territory of its own, the quality of that sovereignty is strained. To avoid a similar conundrum, Vatican City was granted independence, [to] "ensure the absolute and visible independence of the Holy See" and "to guarantee to it an indisputable sovereignty in international affairs" (as explicitly stated in the Lateran Treaty).