The Battle of Issers was a conflict that took place in 1519 between the forces of Sidi Ahmed of Kuku and Hayreddin Barbarossa of the Regency of Algiers. In 1518 Sidi Ahmed and Oruç Reis led a joint expedition against the Spaniards in Tlemcen which failed and resulted in the death of Oruç Reis. Hayreddin Barbarossa resented Sidi Ahmed as his troops had seemingly abandoned Oruç Reis.