Who was Alberto Azzo II, and why is he considered the founder of the House of Este?

Alberto Azzo II (died 1097) was a margrave and a member of the powerful 10th-century Obertenghi dynasty, which held significant wealth and influence across regions including Milan, Genoa, and Lunigiana.1

He is considered the true founder of the House of Este because he established the family's connection to the township and castle of Este, from which the dynasty derived its name. Following the relocation of the Obertenghi to Venetian lands, Alberto Azzo II solidified this identity, and his descendants—specifically through his son Folco I—continued the lineage that eventually rose to prominence in Ferrara and other Italian territories. Additionally, his son Welf IV founded a related branch that led to the dukes of Bavaria, Brunswick, and Lüneburg, as well as the electors of Hanover.12