The Duchy of Bohemia, sometimes also referred to as the Czech Duchy , was formerly part of Great Moravia and became an independent principality in the 9th century. It became part of the Holy Roman Empire from the early 11th century. The Premyslid dynasty which had ruled Bohemia since the 9th century remained in power throughout the High Middle Ages, until the extinction of the male line with the death of Wenceslaus III of Bohemia in 1306. The Duchy of Bohemia was raised to a hereditary kingdom under Ottokar I in 1198.