What it is

The Reichskrone is a crown. The in-game line calls it the emblem of the office of Holy Roman Emperor. It is a historical court artifact tied to that title.
Henry IV holds the Holy Roman Empire in 1066, and Frederick Barbarossa holds it in 1178. The 867 bookmark on the Holy Roman Empire page is East Francia, Lotharingia, and Italy, before that later imperial title.
How to obtain it
Play the emperor, or take the empire from him. In 1066 that seat is Henry IV. In 1178 it is Barbarossa. A court crown moves with the court when the last royal-court title changes hands.
When a bookmark has no Holy Roman Empire title, a missing historical artifact can turn up through an Adventure inspiration. That is the route on a start where the empire has not been formed. Sponsoring the inspiration needs Royal Court or Roads to Power.
The crown equips in the headgear slot. The inventory image shows that slot holding the Monomachus Crown in a different realm. The Reichskrone uses the same slot once you have it.
What it changes
The Reichskrone supports monthly renown, vassal limit, and the opinion of courtiers and guests. It also supports monthly prestige for each powerful vassal who sits on the council.
Read the tooltip for the size of each line. Displaying it in the throne room is a Royal Court feature and feeds court grandeur with the other court pieces.
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