Graziadio Isaia Ascoli (pronounced [ɡrattsja(d)ˈdiːo izaˈiːa ˈaskoli]; 16 July 1829 – 21 January 1907) was an Italian linguist.

One of his most lasting and politically most influential contributions was the coinage of the geographical term Venezia Giulia to denote what was hitherto known as the Austrian Littoral.

Ascoli suggested that northeast Italy was composed of three historically, geographically, and culturally interconnected regions, which he called the Three Venices.

According to his classification, these three historical-geographical regions were: Ascoli coined these names following the internal divisions in the province of Italy during ancient Roman rule, and applied them to the 19th century.

His geographical redefinition had a strong political implication: it was aimed at showing that the peripheral areas of the Austrian Empire were in fact gravitating towards Italy.