count in Swabia who was first mentioned in 842. According to legend, Welf I was a son of Conrad, son of Welf, count of Altdorf, the ancestor of the Burgundian group. This relationship is considered probable because both Conrad and Welf I were counts of Linzgau and Alpgau. The relationship between Welf I and all later members of the Swabian group (Welf, Duke of Carinthia, and his relatives, who were counts of Altdorf) is, again, known only through legend. The Elder House of Welf became extinct when Welf, Duke of Carinthia, died childless in 1055. The property of the House of Welf was inherited by the elder branch of the House of Este that came to be known as the younger House of Welf, or House of Welf-Este. Notable members of the Swabian group Welf I Saint Conrad of Constance Welf, Duke of Carinthia (Welf III) Rulers References Sir Andrew Halliday Annals of the House of Hannover, v.1, London, 1826. at Google Books