Alfonso I

Alfonso I may refer to:

• Alfonso I of Asturias (739–757), king of Asturias
• Afonso I of Portugal (1094–1185), king of Portugal
• Alfonso Jordan (1103–1148), count of Toulouse
• Alfonso I of Aragon (1104–1134), known as Alfonso the Battler, king of Aragon and Navarre
• Alfonso I, Duke of Gandia (1332–1412)
• Alfonso V of Aragon (1396–1458), king of Naples as Alfonso I
• Afonso I of Kongo (1456–1543), first Christian king of the Kingdom of Kongo
• Alfonso I Piccolomini (1468–1498), duke of Amalfi
• Alfonso I d'Este, Duke of Ferrara (1476–1534)
• Alfonso XIII of Spain (1886–1941), known to French Legitimists as "Alphonse I"