The colony at Ceuta rapidly became a drain on the Portuguese treasury, and it was realised that without the city of
Tangier, possession of Ceuta was worthless. After Ceuta was captured by the Portuguese, the camel caravans that were part of the overland trade routes began to use Tangier as their new destination. This deprived Ceuta of the materials and goods that made it an attractive market and a vibrant trading locale, and it became an isolated community. In 1437, Edward's brothers Henry and
Ferdinand persuaded him to launch an attack on the
Marinid sultanate of
Morocco. The expedition was not unanimously supported and was undertaken against the advice of the Pope.
Infante Peter, Duke of Coimbra, and the
Infante John were both against the initiative; they preferred to avoid conflict with the Marinid Sultan. Their instincts proved to be justified. The resulting
Battle of Tangier, led by Henry, was a debacle. Failing to take the city in a series of assaults, the Portuguese siege camp was soon itself surrounded and starved into submission by a Moroccan relief army. In the resulting treaty, Henry promised to deliver Ceuta back to the Marinids in return for allowing the Portuguese army to depart unmolested. Ferdinand, the youngest brother of Edward, was handed over to the Marinids as a hostage for the final handover of the city. ==Late life==