A stem duchy was a constituent duchy of the Kingdom of Germany at the time of the extinction of the Carolingian dynasty and through the transitional period leading to the formation of the Ottonian Empire. The Carolingians had dissolved the original tribal duchies of the Empire in the 8th century. As the Carolingian Empire declined, the old tribal areas assumed new identities. The five stem duchies were Bavaria, Franconia, Lotharingia (Lorraine), Saxony and Swabia (Alemannia). The Salian emperors retained the stem duchies as the major divisions of Germany, but the stem duchies became increasingly obsolete during the early high-medieval period under the Hohenstaufen, and Frederick Barbarossa finally abolished them in 1180 in favour of more numerous territorial duchies.

The Ottonian dynasty was a Saxon dynasty of German monarchs (919–1024), named after three of its kings and Holy Roman Emperors named Otto, especially its first Emperor Otto I. It is also known as the Saxon dynasty after the family's origin in the German stem duchy of Saxony. The family itself is also sometimes known as the Liudolfings, after its earliest known member Count Liudolf and one of its most common given names. The Ottonian rulers were successors of the Germanic king Conrad I, who was the only Germanic king to rule in East Francia after the Carolingian dynasty and before this dynasty.