Alphonse I or Alphonzo I ( 25 July 1109 - 6 December 1185 ) , in Portuguese Afonso I , was the first king of Portugal . He is best known by his prince name Afonso Henriques . Afonso I or Dom Afonso Henriques ( c. 1109 , GuimarÃ # es or Viseu â `` 6 December 1185 , Coimbra ) , more commonly known as Afonso Henriques , nicknamed `` the Conqueror '' , `` the Founder '' or `` the Great '' by the Portuguese , and El-Bortukali ( `` the Portuguese '' ) and Ibn-Arrik ( `` son of Henry '' , `` Henriques '' ) by the Moors whom he fought , was the first King of Portugal .