But it is a long lane that has no turning, and before many months another change came in the kaleidoscope of this young king's fortunes. Pope Innocent the Third had been named by the Empress Constance as guardian of her orphaned boy. To him Walter the Chancellor appealed for aid. Knights and galleys were soon in readiness. Palermo was stormed. Count Diephold was overthrown and imprisoned in the castle dungeon. Kapparon and his Pisan allies and Saracen serfs were driven out of Sicily, and the "Son of Caesar" reigned as king once more. Then came a new alliance. Helped on by the Pope, a Spanish friendship ripened into a speedy marriage. Frederick was declared of age when he reached his fourteenth birthday, and a few months after, on the fifteenth of August, 1209, amid great rejoicings which filled Palermo with brilliancy and crowded its narrow and crooked streets with a glittering throng, the "Boy of Apulia," as he was called, was married to the wise and beautiful Constance, the daughter of Alfonso, King of Arragon. This alliance gave the young husband the desired opportunity; for, with five hundred foreign knights at his back he asserted his authority over his rebellious subjects as King of Sicily. The poor little prince, whose childhood had known only misfortune and unhappiness, became a prince indeed, and, boy though he was, took so manly and determined a stand that, ere the year was out, his authority was supreme from the walls of Palermo to the Straits of Messina. Meantime, in Germany, affairs had been going from bad to worse. Frederick's uncle, Philip of Suabia, had been assassinated at Bamberg, and Otho of Brunswick, head of the House of Guelf, crossed the Alps, was crowned Emperor at Rome in defiance of young Frederick's claim to the Imperial throne, and marched into Southern Italy, threatening the conquest of his boy rival's Sicilian kingdom. Again trouble threatened the youthful monarch. Anxious faces looked seaward from the castle towers; and, hopeless of withstanding any attack from Otho's hardy and victorious troops, Frederick made preparations for flight when once his gigantic rival should thunder at Palermo's gates. "Tidings, my lord King; tidings from the north!" said Walter the Chancellor, entering the king's apartment one bright November day in the year 1211. "Here rides a galley from Gaeta in the Cala port, and in it comes the Suabian knight Anselm von Justingen, with a brave and trusty following. He beareth word to thee, my lord, from Frankfort and from Rome." "How, then; has Otho some new design against our crown?" said Frederick. "I pray thee, good Chancellor, give the Knight of Suabia instant audience." And soon, through the Gothic door-way of that gorgeous palace of the old Norman and older Saracen lords of Sicily, came the bluff German knight Anselm von Justingen, bringing into its perfumed air some of the strength and resoluteness of his sturdy Suabian breezes. With a deep salutation, he greeted the royal boy.