In Western episcopal denominations such as Roman Catholicism and Anglicanism, there’s usually no more than one cathedral per bishopric (there can be more than one “con-cathedral”, but usually it’s because there’s more than one good-sized city in the diocese), because the cathedral is the church where the throne (cathedra) of the bishop is located. Rome itself has only one cathedral: St. John Lateran.
I am therefore curious as to why there are, according to Wikipedia, no fewer than 7 Russian Orthodox cathedrals in Moscow: Christ the Saviour, the Annunciation, the Archangel, Dormition, Elokhovo, Kazan, and St. Basil.
Does each of these cathedrals constitute the seat of a bishop, or does the word “cathedral” have a different meaning in Orthodoxy?
In Russian, these are not all cathedrals; Christ the Saviour is a “chram,” (church or temple), not a “sobor” (cathedral, episcopal seat). As best as I can determine, all of the cathedrals of Moscow are seats of the Patriarch of Moscow, and were built at different times for different reasons, mostly to commemorate things the tsars wanted to commemorate. Three of them are located on Cathedral Square on the grounds of the Kremlin, and two more on Red Square. Elokhovo is the vicarial church of the Patriarch, and Dormitian is the Mother Church. If they weren’t so grand they probably wouldn’t all be called cathedrals, as the term is used in the ROC as it is in the RCC, but part of it is the serial occupation of the cathedrals; when the seat has been moved to a new cathedral, the old building is still called a cathedral.