Between 1325 and 1357, Afonso IV granted public funding to raise a proper commercial fleet and ordered the first maritime explorations, with the help of Genoese sailors under the command of admiral Manuel Pessanha. Forced to reduce their activities in the Black Sea, the Republic of Genoa had turned to the north African trade of wheat and olive oil (valued also as an energy source), and a search for gold, although they also visited the ports of Bruges (Flanders) and England. In 1341, the Canary Islands were officially discovered under the patronage of the Portuguese king, but in 1344 Castile disputed them, further propelling the development of the Portuguese navy.