It all began with the birth of the three children of Loki: Fenrisulfr (Fenrir)The serpent Jörmungandr Hel the queen of all who died from old age or sickness.
The birth of the three children the Æsir of Asgard, came together to discuss what to do with these three extremely dangerous beings. They were going to send the kids away from each other because they were known to be the cause of chaos and would have something to do with the start of Ragnorok.
The Æsir decided to raise the creature and train him to protect the people from Fenrir's terrible fate of death and destruction.
Over the years the leaders of Asgard realized how dangerous and evil Fenrir has grown and they had to make a choice on how to contain him and his powers.
There were three different ways the Æsirs of Asgard tried to contain Fenrir. The first chain was called Leyding. It did not last long because one sharp kick from Fenrir snapped the chain apart. The second attempted Chain was twice as strong as Leyding and was called Dromi; though it took Fenrir longer to break, it still wasn't strong enough.
. By the third attempt the gods knew there skill was not enough to contain Fenrir. Odin, the head of the Æsir, spoke to the dwarves of Svartálfaheimr (the land of the black elves). These dwarves lived underground and were not very pleasant, but they agreed to make a chain powerful enough to keep the giant wolf from escaping.