Pope

Every claim made for the papacy is held to follow from one fact, that the pope is the Bishop of Rome, and the most consequential feature of the office is that nothing stands above it.

What Vatican I defined

Catholic teaching holds that Peter received a primacy from Christ and that the Bishop of Rome inherits it. The First Vatican Council in 1870 defined what this authorises: universal, immediate and ordinary jurisdiction over the whole church, so that the pope can act directly in any diocese without going through its bishop, and infallibility when he defines a doctrine of faith or morals to be held by the whole church. That last power is narrow and has been used sparingly; the usual reckoning is that it has been exercised unambiguously once since it was defined, for the Assumption in 1950.

No mechanism of removal

A pope holds office until death or resignation. Resignation is provided for in canon law and is rare, Benedict XVI in 2013 being the first to resign freely since Celestine V in 1294. There is no mechanism for removing a pope, which is a structural fact of consequence: the see that judges all is judged by none. The Orthodox churches accept the Bishop of Rome as first in honour among patriarchs and reject the jurisdictional and infallible claims, and that rejection is the substance of the schism rather than an ornament on it.

Papal primacy was not asserted all at once. Early bishops of Rome exercised real but limited influence beyond their own see, and the claims that later hardened into full jurisdictional authority developed over centuries through crises, the fall of the western empire, disputes with Constantinople that ended in the mutual excommunications of 1054, the Avignon papacy of the fourteenth century when popes lived in France under French influence, and the Western Schism that produced three rival claimants at once before the Council of Constance resolved it in 1417.

The loss of the Papal States to a unified Italy in 1870, in the same year Vatican I defined papal infallibility, stripped the papacy of the temporal kingdom it had held for a thousand years and left it, after decades of self-imposed confinement to the Vatican, as a purely spiritual and moral authority projected through travel and media rather than armies. That shift shapes the modern office: twentieth and twenty-first century popes have travelled further and spoken to more people than any predecessor, and the see has increasingly been held by men from outside Italy, a Pole in 1978, a German in 2005, and an Argentine in 2013, the first pope from the Americas, reflecting a Catholic population now concentrated well outside Europe.