The Palazzo dei Normanni or Royal Palace of Palermo is a palace in Palermo, Italy. It was the seat of the Kings of Sicily during the Norman domination and served afterwards as the main seat of power for the subsequent rulers of Sicily. Since 1946 it has been the seat of the Sicilian Regional Assembly. The building is the oldest royal residence in Europe; and was the private residence of the rulers of the Kingdom of Sicily and the imperial seat of Frederick II and Conrad IV.