The biscione (Italian pronunciation: [biʃˈʃone]; in Milanese as the bissa), also known as the vipera ("viper"), is a heraldic charge showing on argent an azure serpent in the act of consuming a human; usually a child and sometimes described as a Moor or an Ottoman Turk. It was the emblem of the House of Visconti from the 11th century, becoming associated with Milan as the Visconti gained control over the city in 1277.
Visconti is the family name of two important Italian noble dynasties of the Middle Ages. There are two distinct Visconti families: the first one (chronologically) in the Republic of Pisa in the mid twelfth century who achieved prominence first in Pisa, then in Sardinia, where they became rulers of Gallura. The second family rose to power in Milan, where they ruled from 1277 to 1447, and where several collateral branches still exist. Pope Gregory X, who reigned from 1271 to 1276, was a member of the Visconti family of Milan.