| Anna Jagiellon | |
|---|---|
 Queen Anna in her coronation robes (1576 painting by Martin Kober) | |
| Queen of Poland Grand Duchess of Lithuania | |
| Reign | 15 December 1575 – 19 August 1587 |
| Coronation | 1 May 1576 in Kraków |
| Predecessor | Henry of Valois |
| Successor | Sigismund III Vasa |
| Co-monarch | Stephen Báthory (1576–1586) |
| Born | 18 October 1523 Kraków, Kingdom of Poland |
| Died | 9 September 1596 (aged 72) Warsaw, Polish–Lithuanian Commonwealth |
| Burial | |
| Spouse | |
| Dynasty | Jagiellon |
| Father | Sigismund I the Old |
| Mother | Bona Sforza |
| Religion | Roman Catholicism |
| Signature |  |
Anna Jagiellon (Polish: Anna Jagiellonka, Lithuanian: Ona Jogailaitė; 18 October 1523 – 9 September 1596) was King of Poland and Grand Duke of Lithuania from 1575 to 1587.
Daughter of Polish King and Lithuanian Grand Duke Sigismund I the Old and Italian duchess Bona Sforza, Anna received multiple proposals, but remained unmarried until the age of 52. After the death of King Sigismund II Augustus, her brother and the last male member of the Jagiellonian dynasty, her hand was sought by pretenders to the Polish-Lithuanian throne to maintain the dynastic tradition. Along with her then-fiancé Stephen Báthory, Anna was elected as co-ruler in the 1576 royal election of the Polish–Lithuanian Commonwealth. Their marriage was a formal arrangement and distant.
While Báthory was preoccupied with the Livonian War, Anna spent her time on local administrative matters and several construction projects, including the city wall Stara Prochownia to protect Sigismund Augustus Bridge. After her husband's death in December 1586, Anna had the opportunity to remain on the throne as the sole ruler, but instead promoted her nephew Sigismund III Vasa, whose reign established the House of Vasa on the Polish-Lithuanian throne for the next eighty years (1587–1668).