Prior to the phylloxera epidemic of the 19th century, Bonarda was speculated to have accounted for 30% of the plantings in Piedmont but today is only found in scattered plantings along the left bank of the Tanaro river near Govone.
Around the communes of Novara, Pavia and Vercelli, Uva Rara is known as Bonarda which has led it to be confused with many of the other grape varieties known as Bonarda, particularly Bonarda Piemontese.