Ever since 711 AD, Lisbon had been a strategic port city ruled by the Moors, who had expanded their territory in South-West Europe. Their rule ceased in 1147 with the arrival of Afonso Henriques and the siege of Lisbon, which lasted for about four months and brought the city under Portuguese control. Afonso became the first King of Portugal and his victory was seen as a successful moment of the wider Reconquista, which marked the period of expansion of the Christians over the Iberian Peninsula and their struggle to drive away the Moorish overlords.