| Peter III | |
|---|---|
 Detail from the Nuova Cronica | |
| King of Aragon and Valencia Count of Barcelona | |
| Reign | 27 July 1276 – November 1285 |
| Predecessor | James I |
| Successor | Alfonso III |
| King of Sicily (jure uxoris) | |
| Reign | 4 September 1282 – November 1285 |
| Predecessor | Charles I |
| Successor | James I |
| Co-ruler | Constance II of Sicily |
| Born | c. 1239 Valencia, Aragon |
| Died | November 1285 (aged 45–46) Vilafranca del Penedès, Catalonia, Aragon |
| Burial | |
| Spouse | |
| Issue more... | |
| House | Barcelona |
| Father | James I of Aragon |
| Mother | Violant of Hungary |
Peter III of Aragon (In Aragonese, Pero; in Catalan, Pere; in Italian, Pietro; c. 1239 – November 1285) was King of Aragon, King of Valencia (as Peter I), and Count of Barcelona (as Peter II) from 1276 to his death. At the invitation of some rebels, he conquered the Kingdom of Sicily and became King of Sicily in 1282, pressing the claim of his wife, Constance II of Sicily, uniting the kingdom to the crown.