archbishop of Reims who, by declaring the Frankish crown to be elective rather than hereditary, paved the way for the accession of Hugh Capet in place of the Carolingian claimant, Charles, Duke of Lower Lorraine.

Adalbero, a native of Lorraine, had opposed the attempts of the Carolingian king of France, Lothair (Lothar), to gain Lorraine from the Holy Roman emperor Otto II. Accused of treason, he was summoned by Louis V (986–987), Lothair's son and successor, to appear at an assembly of the leading Franks at Compiègne. But Louis's sudden death prevented the trial from taking place; instead, Adalbero denounced Charles (Charles I) of Lorraine, uncle of Louis, as unfit to succeed to the Frankish throne and supported the candidacy of Hugh Capet. Duly elected, Hugh was crowned by Adalbero in July 987 at Noyon.