Moulay Ismail set off on a campaign with an army of more than 20,000 men.[3] He launched several raids against the Beni Amer and the other Algerian tribes, as to push them back.[4] Oran itself was commanded by the Andrés Copola, Duke of Canzano.[5] Moulay Ismail attempted a swift attack on 20 July, followed by another attempt on 24 July, both of which failed in the face of heavy artillery fire from the square and the firm defence of the Spanish garrison.