What it is

The Papal Tiara is a crown tied to the Papacy. The in-game line calls it the jeweled mitre with a golden crown that symbolizes the papal office.
It is a historical artifact. The pope who holds the Papacy at the bookmark is the one who starts with it. Faith and conversion is the page for county conversion and holy wars around that seat.
How to obtain it
Start as the pope, or take the Papacy. A claim, a scheme, or a war against the current holder are the other routes. The steal scheme in the store image is the shape of an artifact claim. The numbers on that window are for the scheme in the shot.
The crown can leave the Papacy. A coronation gift has put it on a secular ruler in play. While you hold it without the papal title, the effect line changes. See below.
If the Papacy title is missing from a start, a missing historical artifact can turn up through an Adventure inspiration. Sponsoring that inspiration needs Royal Court or Roads to Power.
What it changes
While the holder is theocratic, the tiara supports monthly piety and learning lifestyle experience. While the holder is not theocratic, it supports monthly prestige instead.
A king who holds the tiara gets the prestige line. A theocratic holder gets the piety and learning lines. The tooltip on the crown shows which branch is active. Display in the throne room still feeds court grandeur under Royal Court.
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