Before the battle of Nájera began, the prince prayed aloud to God that as he had come that day to uphold the right and reinstate a disinherited king, God would grant him success. Then, after telling Peter that he should know that day whether he should have his kingdom or not, he cried: "Advance, banner, in the name of God and St. George; and God defend our right". The knights of Castile attacked and the English vanguard, but the wings of Henry's army failed to move, so that the Gascon lords were able to attack the main body on the flanks. Then the prince brought the main body of his army into action, and the fighting became intense, for he had under him "the flower of chivalry, and the most famous warriors in the whole world". At length Henry's vanguard gave way, and he fled from the field.