After the fall of Tenochtitlan in 1521 conqueror Hernán Cortés exercised power in New Spain as its first European governor and proceeded to allocate rewards to Spaniards who had participated in the victory. He initially established a government in the town of Coyoacán, south of Lake Texcoco, because Tenochtitlan was in ruins after the conquest. From here he governed with the title of Captain General and "Justicia Mayor". In his letters to the king, he explained and justified his actions, arguing that it was necessary to grant rewards of encomiendas to conquerors in order to persuade them to remain in the area now under Spanish control rather than see them depart for conquests elsewhere.