Sigurd Ragnarsson, the Prophecy, and the Mark of Fafnir Dragon

In the tale of Ragnar and his sons, Ragnar had a son named Sigurd. What's most exciting about this figure is the mark in his eye. Their father was great and so were the sons. 

Ragnar Lothbrok had many wives and children. One of them was the beautiful lady Aslaug who declared herself a volva. Sigurd was a son of Aslaug and Ragnar. Aslaug was not only beautiful but also wise as she could see things that other people couldn't see. 

Aslaug and Ragnar Lothbrok (Cre: "Vikings" TV series)

Legend had it that Aslaug was the daughter of Sigurd the Dragon Slayer and the valkyrie Brynhildr. The legend of Sigurd the Dragon Slayer was popular back then and was often carved onto the runestone. Sigurd once encountered the Dragon Fafnir. With the bravery, great fighting skills, and wisdom, Sigurd killed Fafnir with his own sword forged by his foster father. 

Regarding Aslaug and Ragnar Lothbrok, Aslaug fell for Ragnar as he could prove himself brave and wise. 

According to the legend, Ragnar once visited a neighboring country and met the king there. The king persuaded Ragnar to abandon Aslaug and marry his daughter. Three birds came home to inform Aslaug of Ragnar's plan. 

Because of this, Aslaug could no longer hide her noble origins. She revealed to her husband that she was the daughter of Sigurd the Dragon Slayer and Brynhild the Valkyrie. And to prove this, she would bear Ragnar a son who would bear a mark of a dragon that Sigurd killed. The dragon was actually the Dragon Fafnir in Norse mythology who turned himself into a dragon to guard his own treasure.

Sigurd Snake-in-the-eye with the physical trait inside his eye

Among many sons of Ragnar, Sigurd was the most connected with his father. They had a very good relationship and Ragnar Lothbrok often brought this son on his voyage. On hearing the news of Ragnar's death, Sigurd cut himself to the bone as he couldn't bear it that his beloved father was no longer with him.