In a dungeon in the castle of Cleves lay Elsa of Brabant, languishing in captivity. Her father, the Duke of Brabant, had ere he died appointed his most powerful vassal, one Frederick of Telramund, to be her guardian; but he, seeking only the advancement of his own ends, shamefully abused the confidence of his lord. Using his authority as Elsa's guardian, he sought to compel her to become his wife, and threw her into prison to await the wedding-day, knowing well that none would dare to dispute his action. An appeal was made on Elsa's behalf to the Emperor, Henry I, who decreed that she should choose a champion, so that the matter might be settled by combat. But, alas! there was not a knight who would venture to match his skill against that of Frederick, who was a giant in stature and an expert in sword-play. In accordance with the Emperor's decree Telramund sent out a herald at stated times to proclaim his readiness to do battle with any who would champion the cause of Elsa. Time passed, yet the challenge was not accepted, and at length the day was fixed for the bridal. Behind her prison bars the lady wept ceaselessly, and called upon the Virgin to save her from the threatened fate. In her despair she beat her breast with her chaplet, whereon was hung a tiny silver bell. Now this little bell was possessed of magic properties, for when it was rung the sound, small at first as the tinkling of a fairy lure, grew in volume the further it travelled till it resembled the swelling of a mighty chorus. Rarely was its tone heard, and never save when its owner was in dire straits, as on the present occasion. When Elsa beat her breast with it, therefore, its magical qualities responded to her distress, and its faint, sweet tinkle fell on her ear. Far away over hill and dale went the sound of the bell, growing ever richer and louder, till at length it reached the temple where Parsifal and his knights guarded the Holy Grail. To them it seemed that the swelling notes contained an appeal for help directed to the Holy Vessel over which they kept vigil. While they debated thereon a loud and mysterious voice was heard bidding Parsifal send his son Lohengrin to the rescue of Elsa of Brabant, whom he must take for his wife, yet without revealing to her his identity. The awed knights recognized the voice as that of the Holy Grail, and Lohengrin at once set out, bound he knew not whither. When he reached the shores of the Rhine he found awaiting him a boat drawn by a stately swan. Taking it as a sign from Heaven, he stepped into the little boat and was carried up the Rhine, to the sound of the most exquisite music.