A few years later Frederick, in order to carry out his plans with regard to Italian lands, appointed his ten-year-old son as King of Rome and as his successor to the German Empire. Then leaving the young King in Germany under the guardianship of Bishop Engelbert of Cologne, he went to Italy, and was crowned Emperor by the Pope. Young Henry held his court in Nuremberg in 1225. In the castle, in November, a double festival was celebrated--the marriage of the young King with Margaret, daughter of Duke Leopold of Austria, and of the brother of the bride, Duke Henry of Austria, with Agnes, a daughter of the Landgraf Hermann von Thüringen. At this double wedding, as some chroniclers aver, or at the wedding of Rudolph von Hapsburg (1284), as is more probable, a terrible catastrophe occurred. For just as the numerous assembly of nobles and ladies had begun to dance in the hall, the platform erected for spectators fell in, and about seventy nobles, knights, and girls were crushed to death. It was certainly in the middle of this festival that the horrible news arrived that the Archbishop of Cologne, the young King's adviser, had been murdered, from motives of revenge, by his nephew, Duke of Isenburg. "Such deeds were then very frequent," says the Abbot Conrad von Lichtenau, "because the doers thereof hoped to obtain pardon by a pilgrimage to the Holy Land." Three days after his marriage the young King had to sit in judgment on the culprit at the Kaiserburg. Deeply moved, he asked the noble Gerlach von Büdingen for his opinion. Ought the murderer to be outlawed, there and then? Gerlach answered yes, for the crime was patent. Friedrich von Truhendingen opposed him violently, however, maintaining that the accused man ought to be first produced, as justice and custom demanded. Gerlach became enraged. The argument grew hot, and presently, in spite of the King's presence, the supporters of either opinion seized their arms and came to blows. A fearful crush occurred on the stairs, which gave way under the weight of struggling humanity, and some fifty people were killed upon the spot. But the sentence of outlawry got itself pronounced, and a decree of excommunication followed from the Church. This was but one example of the lawlessness of the times. Violence was not often so swiftly punished. Germany had fallen on evil days, and worse were in store for her. The absenteeism of her Emperors was producing its inevitable result.