The first event is said to have occurred when the African Berbers/Moors conquered the Iberian Peninsula (present-day Portugal and Spain). Back then the conquered territory was identified as Andalusia
The Ottoman Turks controlled the main overland routes to the Orient, and subsequently denied the Christian West passage to the east indies.
These ships and men that were given to him by the king and queen and his promises to them set the stage for his four voyages. All of them eventually had some sort of disaster. They began with his maiden voyage in 1492 which was disaster number one.