The Battle of Tejo took place on July 1384, in the Tagus river (Tejo in Portuguese), between a Portuguese naval force of 34 ships (5 of which were major vessels) with the objective of supplying the besieged city of Lisbon with much needed supplies and the Castilian fleet led by Sanchez de Tovar. Although the Portuguese lost three ships (Castilian casualties are unknown), Portuguese success in reaching Lisbon and giving it the much needed supplies was a major victory for Portugal.