Lothair (French: Lothaire; Latin: Lothārius), sometimes called Lothair III or Lothair IV, was the Carolingian king of West Francia from 10 September 954 until his death in 986.
Lothair was born in Laon near the end of 941, as the eldest son of king Louis IV and Gerberga of Saxony. He succeeded his father on 10 September 954 at the age of thirteen and was crowned at the Abbey of Saint-Remi by Artald of Reims, Archbishop of Reims on 12 November 954. Lothair had already been associated with the throne since the illness of his father in 951, this being a custom in the royal succession since the founding of the Kingdom of the Franks by the Merovingian dynasty.
In early 986 Lothair intended to attack Cambrai, an imperial city but one dependent on the Archbishoprics of Reims and Liège; he thought that he could convince Bishop Rothard to surrender the city in exchange for his appointment as Archbishop of Rheims (following the deposition of Adalberon) and Prince-Bishop of Liège (whose Prince-Bishop Notger finally escaped to Ottonian territory); but the King suddenly died at Laon on 2 March 986. He received a magnificent funeral and was buried next to his father Louis IV in the choir of Saint-Remi of Reims.