"the Visconti family"

The crest of the Visconti of Gallura (Pisa and Sardinia)
Public DomainThe crest of the Visconti of Gallura (Pisa and Sardinia) - Credit: Fabiocarboni
There were two Visconti dynasties who were prominent in Italy in the Middle Ages. This probably refers to the Visconti family of Pisa who also had a family branch in Sardinia. The patrician of the Pisan Visconti clan was Alberto; his grandchildren Lamberto and Ubaldo I brought the dynasty to its height in the late 12th century. Both of them held control over Pisa until around 1213 when power was divided between four families and the power of the Viscontis diminished greatly.