He was only two years old at the death of his father, Henri of
          Burgundy, conqueror and first count of Portugal, so that the
          management of affairs fell to his ambitious and dissolute mother,
          Teresa of Castile. Wresting the power from her in 1128, he turned his
          sword against the Moors, defeated them at Ourique, 25 July 1139, and
          proclaimed himself king on the field of battle. He took Lisbon (1147),
          and later, all Galicia, Estremadura and Elvas.
 

Source: Leo van de Pas