But there was a wonderful change still to befall him.  Cassander’s sons,—as has been said, were disputing for the kingdom.  Their mother, Thessalonica, a daughter of Philip of Macedon, favoured the youngest, and this so enraged the eldest that he killed her with his own hand.  His brother called on Demetrius to help him, and he came with his army; but on some fancy that the youth was plotting against him, he had him put to death, and convinced the Macedonians that the act was just.  They would not have the murderer of his own mother as their king, but chose Demetrius himself to be king of Macedon, so that almost at the same time he lost one kingdom and gained another, and this last remained in his family for several generations.  He tried to regain Asia, but did not succeed; indeed he was once again obliged to fly from Macedonia in disguise.  He had learned to admire the splendours of the East, wore a double diadem on his head, and wonderful sandals; and he had also ordered skilful weavers and embroiderers to make him a mantle, on which the system of the universe as then understood—the earth in the centre, with the moon, sun, and planets, and every fixed star then discovered—was to be embroidered in gold.