The Czech state, formerly known as Bohemia (Čechy), was formed in the late 9th century as Duchy of Bohemia, at that time under the dominance of the powerful Great Moravian Empire. After the 10th century the territory of Slovakia was gradually integrated into the Kingdom of Hungary, which itself became part of the Austro-Hungarian Empire or Habsburg Empire. After the fall of the Empire in 907, the centre of power was transferred from Moravia to Bohemia under the Přemyslids. In 1004, the duchy was formally recognized as a part of the Holy Roman Empire, rising to the status of Kingdom of Bohemia in 1212. During the rule of the Přemyslids and their successors, the Luxembourgs, Bohemia expanded in size until reaching its greatest territorial extent in the 14th century.