Realistically, I'd carry a spear and a shield (if I was lucky) because it was the spear, more than any other weapon, that decided the outcome of a battle. The sword may indeed be the queen of weapons and a good thing to have around when the fighting truly gets close (too close for a spear), but until that happens, I'd place my bet on a stout spear and solid shield.
Were I not doomed to be among the fodder, I'd obviously want to be a Knight armed with a lance with a trusty steed. Even in 1257, I could count on my armor to make me all but impervious to many of the dangers on the battlefield and since I was clearly born to rule and fight my own martial prowess and quality weaponry would give me such an advantage on the barely trained rank and file that they would be mere chaff in the wind before me. And, should my horse or lance fail me, I'd opt for a flanged mace. Small enough to carry on your person when armed with heavier weapons, the flanged mace represents one of the most efficient bludgeons in history - able to tear flesh, break bones and crumple armor with relative ease.