One of his vassals, Hagen von Tronje, a man in black with an iron helm adorned with raven's feathers, makes a proposal: Siegfried will marry Kriemhild if he helps Gunther to obtain the hand of Brunhild.

She gives birth to a child conceived with Siegfried and she also decides to distribute the gold from the Nibelungen treasure, inherited from her husband, to the population, in order to turn them against Gunther and Hagen.

When Kriemhild decides to flee to Xanten, Hagen and Gunther agree to kidnap Siegfried's son and have him brought up in a monastery, so that one day he cannot be dangerous to them or lay claims to the throne.

Margrave Rüdiger saves Kriemhild and brings her to the Danube, where she accepts King Etzel's marriage proposal in order to carry out her revenge against Hagen.

On the road that takes them from Worms to Hungary, where Etzel and his court reside, Hagen talks to water fairies, who tell him that none of them will return alive except the chaplain.

Kriemhild offers to let Gunther and her other relatives leave in exchange for Hagen's head, but they all refuse, so she orders to set on fire the palace where they are entrenched.

Rüdiger's daughter Hildegund and the minstrel Volker von Alzey, who was blinded during the fight, are the only Burgundians to embark on the long march back home.

In the late 1950s, German producer Artur Brauner had wanted Fritz Lang to remake his own silent film and had already informed the press that the project would go ahead.

[3]: 147  But it was the vast box office success of his three films (1963, 1964, 1965) based on Karl May's Winnetou character that convinced Brauner that Reinl was the right man for the job.

Brauner wanted a disciplined worker who would respect budgets even without constant direct control by the producer, who could deal with large numbers of extras and who had experience shooting in Yugoslavia.

Reinl also was fond of impressive landscape shots and, in conjunction with a symphonic music score, these were supposed to add gravitas to the story.

[1] Locations included what was then Yugoslavia[1] (today's Serbia: Sremska Rača, Smederevo fortress and Slovenia: Postojna Cave) as well as Iceland,[1] and Spain[1] (Ciudad Encantada and Cuenca).

However, this was the limit of the cooperation with Avala and the total cost of Die Nibelungen reportedly came to 8 million DM, which would have made it the most expensive post-war film in West Germany at the time.

[3]: 147 According to a survey conducted by the Allensbach Institute prior to shooting, 35% of respondents wanted to see a movie about the hero Siegfried, but he had to be blonde and played by an unknown actor.

[5] The Lexikon des internationalen Films found "familiar motifs from the Nibelungenlied as material for a naive-elaborate, at times comical, adventure series in picture-book style".