Alfonso III (Spanish) or Afonso III (Portuguese) may refer to:
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Alfonso III of Asturias (866–910), surnamed "the Great"
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Afonso III of Portugal
Afonso III (; rare English alternatives: ''Alphonzo'' or ''Alphonse''), or ''Affonso'' (Archaic Portuguese), ''Alfonso'' or ''Alphonso'' ( Portuguese-Galician) or ''Alphonsus'' (Latin), the Boulonnais ( Port. ''o Bolonhês''), King of Portugal ...
(1210–1279)
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Alfonso III of Aragon
Alfonso III (4 November 1265, in Valencia – 18 June 1291), called the Liberal (''el Liberal'') or the Free (also "the Frank," from ''el Franc''), was the king of Aragon and Valencia, count of Roussillon, Cerdanya and Barcelona (as ) from 12 ...
(1285–1291)
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Alfonso III d'Este, Duke of Modena
Alfonso III d'Este (22 October 1591 – 26 May 1644) was Duke of Modena and Reggio from 1628 to 1629. He was the husband of Princess Isabella of Savoy, daughter of Charles Emmanuel I, Duke of Savoy and his wife Infanta Catherine Michelle of Spain ...
and Reggio (1628–1644)
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Afonso III of Kongo Afonso III Mvemba a Nimi (also spelt Affonso III) was a ruler of the kingdom of Kongo during its civil war period.
King Afonso III first enters written record as the ruler of the Marquisate of Nkondo. He governed that area from late 1669 until mid ...
(1666–1667)
{{Human name disambiguation, Alfonso 03