Welf, Duke of Carinthia

Welf III
Duke of Carinthia
Duke Welf in the Weingarten Stifterbüchlein, c. 1510
Noble family	Elder House of Welf
Father	Welf II, Count of Altdorf
Mother	Imiza of Luxembourg
Died	13 November 1055 Bodman Castle
Buried	Weingarten Abbey

Welf III (died 13 November 1055), the last male member of the Swabian line of the Elder House of Welf, was Duke of Carinthia and Margrave of Verona from 1047 until his death.

Welf III was the only son of the Swabian count Welf II of Altdorf (d. 1030) and Imiza, a daughter of Count Frederick of Luxembourg and niece of the later empress Cunigunde of Luxembourg. His sister Kunigunde of Altdorf (c. 1020 – 1054) married Margrave Albert Azzo II, of Milan, a member of the Italian House of Este, and became the ancestor of the House of Welf-Este of (Younger) House of Welf.

Upon the death of his father, Welf III succeeded him in the family's extended estates in Swabia and Bavaria. Through the intervention of his aunt, Richlind of Altdorf, he also inherited the property of her late husband Count Adalbero II of Ebersberg in 1045. Probably through his mother, Imiza's, intervention Emperor Henry III enfeoffed Welf with the princeless Duchy of Carinthia and the adjacent March of Verona, which after the death of Duke Conrad the Younger in 1039 both had been held personally by the Salian emperor.

Together with Duke Bretislaus I of Bohemia, Welf accompanied Emperor Henry III on his 1051 campaign against King Andrew I of Hungary. Later however, he turned against the emperor and got involved in a conspiracy around the deposed Duke Conrad I of Bavaria, who with Hungarian support raided the Carinthian March of Styria. A plot to assassinate Henry failed, when Duke Welf became confined to his sickbed and revealed the plans.