Zwentibold (870 – August 13 900) was the illegimate son of the Holy Roman Emperor, Arnulf of Carinthia. In 895 his father granted him the Kingdom of Lotharingia, which he ruled until his death.

He had great problems controlling the nobility. In 899 Arnulf died and his legitimate son Louis III became German king. Zwentibold attempted to take advantage of the succession to establish complete independence for his kingdom. However, the nobility supported Louis and asked him to intervene. In 900, Reginar (also known as Rainier), count of Hainaut rose against Zwentibold and slew him near present-day Susteren. Zwentibold was the last Lotharingian king; he was replaced by a German court with the noble Gebhard of Franconia as Duke of Lotharingia .