Imperial Cathedrals

Imperial Cathedral (German: Kaiserdom) is the designation for a cathedral linked to the Holy Roman Emperors (Kaiser).

The three Romanesque cathedrals of Mainz, Worms and Speyer on the Upper Rhine are called Rhenish Imperial Cathedrals.

The construction of Mainz Cathedral was begun about 975 under Archbishop Willigis, then regent of the Holy Roman Empire for minor King Otto III. His seat was already meant as a kind of "state church", it was the first building of this size north of the Alps. The cathedral was completed in 1009, burnt down at the dedication, and was immediately rebuilt. Willigis may have planned to replace Aachen Cathedral as coronation church of the King of the Romans; indeed Otto's III successors Henry II (in 1002) and Conrad II (in 1024) were crowned in Mainz, but both presumably in the preceding building, since the present cathedral was not consecrated until in 1038. King Henry IV also contributed to the building after another blaze in 1081. Mainz Cathedral was the coronation site for Philip of Swabia, for Frederick II, and anti-king Henry Raspe.

Speyer Cathedral is the world's largest preserved Romanesque church (after the demolition of Cluny Abbey) and today a UNESCO World Heritage Site. It was built starting about 1025 by King Conrad II as a family vault for the ruling Salian dynasty. His successor Henry III donated the Speyer Gospels in 1046; the building was completed in 1061 under the rule of King Henry IV. During the Investiture Controversy with Pope Gregory VIII, he had the church again extended from 1081, in order to stress his Imperial authority. His mortal remains were transferred to the cathedral by his son Henry V in 1111.

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