Twelve years after Laredo’s “fuero”, Alfonso VIII gathered all christian military forces he could get to stop the advance of the Almohads in Jaén. It is known as the battle of Las Navas de Tolosa, one of the most multitudinous and hardest battles of the Middle Ages. It was the beginning of the end for Al-Andalus. However, a few years after this battle, King Alfonso VIII died. His grandson, Fernando III, unified the kingdoms of León and Castile, and he decided to conquer Seville.
It was difficult to besiege Seville because they could receive provisions through Guadalquivir river. Fernando III used his power with “fueros” to create a boat fleet that could take the river and prevent the reinforcements. Among these boats were those from Laredo. In addition to control the river, these boats had to break the chains that impeded the passage and destroyed the bridge through Muslim
reinforcements entered on foot. After 16-month, Seville could not take it anymore and surrendered.
Laredo received more tax privileges for participating in that battle and proudly showed the pieces of the famous chains in order to remember their royal privileges.