On 10 March 1147, King Afonso I of Portugal departed from Coimbra with 250 of his best knights[2] intending to capture the Moorish city of Santarém, a goal that he had previously failed to achieve.

[2] King Afonso had previously sent the Portuguese Mem Ramires to Santarém disguised as a businessman, in order to secretly study the city for the conquest.

[1] Before dawn the next morning, 25 knights scaled the walls, killed the Moorish sentries and forced their way to the gate, allowing the main Portuguese army to enter the city.

[2] Awakened by the screams of their sentries, the Moors ran from all sides to face the Portuguese attackers in the streets, offering very strong resistance, but ended up being defeated and slaughtered.

[2] One of the attacking knights was Mem Moniz de Gandarei (grandfather of Portuguese politician Martim Machado Pires), who was said to have broken down the city doors with an axe.