Sigebert (which means roughly "magnificent victory"), also spelled Sigibert, Sigobert, Sigeberht, or Siegeberht, is the name of:

Frankish and Anglo-Saxon kings

• Sigobert the Lame (died c. 509), a king of the Franks
• Sigebert I, King of Austrasia (reigned 561–575)
• Sigebert II, King of Austrasia and Burgundy (reigned 613)
• Sigebert III, King of Austrasia (reigned 634–656)
• Sigeberht the Little, King of Essex (reigned 623?–653)
• Sigeberht the Good, a king of Essex (reigned c. 653–660)
• Sigeberht of East Anglia, saint and a king of the East Angles (reigned c. 629–c. 634)
• Sigeberht of Wessex, King of Wessex (reigned 756–757)

Others

• Sigebert of Gembloux (c. 1030–1112), Belgian medieval author and historian
• Sigebert Buckley (c. 1520–probably 1610), Benedictine monk in England
• Sigebert IV, fictitious son of the Merovingian king Dagobert II