Bona Sforza

Bona Sforza
Cameo with bust of Bona Sforza, c. 1540
Queen consort of Poland Grand Duchess consort of Lithuania
Tenure	18 April 1518 – 1 April 1548
Coronation	18 April 1518 Kraków, Poland
Duchess regnant of Bari
Tenure	11 February 1524 – 1557
Predecessor	Isabella
Successor	None (annexed by Naples)
Born	2 February 1494 Vigevano, Duchy of Milan
Died	19 November 1557(1557-11-19) (aged 63) Bari, Kingdom of Naples
Burial	Basilica di San Nicola
Spouse	Sigismund I of Poland ​ ​ (m. 1517; died 1548)​
Issue Detail	Isabella, Queen of Hungary Sigismund II Augustus, King of Poland Sophia, Duchess of Brunswick-Lüneburg Anna, Queen of Poland Catherine, Queen of Sweden
House	Sforza
Father	Gian Galeazzo Sforza
Mother	Isabella of Aragon

Bona Sforza (2 February 1494 – 19 November 1557) was Queen of Poland and Grand Duchess of Lithuania as the second wife of Sigismund the Old, and Duchess of Bari and Rossano by her own right. She was a surviving member of the powerful House of Sforza, which had ruled the Duchy of Milan since 1447.

Smart, energetic and ambitious, Bona became heavily involved in the political and cultural life of the Polish–Lithuanian union. To increase state revenue during the Chicken War, she implemented various economic and agricultural reforms, including the far-reaching Wallach Reform in the Grand Duchy of Lithuania. In foreign policy, she allied with the Ottoman Empire and sometimes opposed the Habsburgs. Her descendants became beneficiaries of the Neapolitan sums, a loan to Philip II of Spain that was never completely paid.