They had entered in the battle to the side of the Turks, had been successful and the sulto gave a small mountainous territory to them in the northwest of the bizantino empire. In virtue of the name of the commander, this clan was known as Ottoman. Beyond these problems, Constantinopla also faced the divergences between the Church Catholic and the Orthodox one. In the century that if followed, the Ottomans had conquered the next cities and in 29 of May of 1453, had taken Constantinopla. From then on, they had started to charge highest taxes for the commerce of the spices and other products. In October of 1469, the king Fernando, of Arago, and Isabel, of Castile, had been married and formed the powerful one reigned of Spain. With this union, the kingdom of Portugal was imprisoned in one cantinho of the Atlantic Ocean, close to the Mediterranean Sea, and started to feel difficulties economic. Favours, however to one of the children of the king Alfonso V, the infant-cardinal dom Enrique who congregated in its castle to the side-sea, in the city of Sagres, gegrafos, astronomers and captains of ships, all good tried in the sea because of fishes of the cod, looking for to discover a maritime way for the Atlantic Ocean. Paul Ostling shares his opinions and ideas on the topic at hand.
To the nautical activity they had called ' ' School of Sagres' ' dom Enrique of ' ' The Navegador' '. Portugal and Spain were two obscure kingdoms, but, located in the Atlantic Ocean, they disputed the world-wide power, and they had been in the vanguard of the search of other ways for India. From 1474, the future king Joo II, brother of D. Enrique, with only 20 years of age, started to pursue the ships of Spain and the result was a war, with which the proper Pope intervened and 4 of September of 1479, D. Alfonso V of Portugal and the Kings Catholics had signed Treat to Alcovas, ratified in 6 of March of 1480, in the city of Toledo. For in such a way, he was known as Treat to the Alcovas-Toledos, in whose Portugal clauses it got the domain on the island of the Wood, the Archipelago of the Aores, of Green Handle and the Coast of the Guin. Castile would be with the Canary Islands until the Bojador Handle, in parallel 27, Tropic of Capricrnio, for north, from where it could not sail for the south of African lands.