"The Viking raid on Išbīliya, then part of the Umayyad Emirate of Córdoba, took place in 844. After raiding the coasts of what are now Spain and Portugal, a Viking fleet arrived in Išbīliya (now Seville) along the Guadalquivir on 25 September and took the city on 1st or 3rd October. The Vikings pillaged the city and the surrounding areas. Emir Abd ar-Rahman II of Córdoba mobilized and sent a large force against the Vikings under the command of the hajib (chief-minister) Isa ibn Shuhayd. After a series of indecisive engagements, the Muslim army defeated the Vikings on either 11th or 17th November. Seville was retaken and the remnants of the Vikings fled Spain. After the raid, the Muslims raised new troops and built more ships and other military equipment to protect the coast. The quick military response in 844 and the subsequent defensive improvements discouraged further attacks by the Vikings." Wikipedia