Born near Settimo Pavese, Bianca Maria was the illegitimate daughter of Filippo Maria Visconti,[REF] Duke of Milan and last of the Visconti rulers, and Agnese del Maino, the only person the shy, secluded Filippo ever loved.
When she was six months old, Bianca Maria and her mother were sent to a castle in Abbiate, where a rich residence had been established for the two of them.