We know what the ice king's crown is where it came from and what it did to him but we don't know who made it. It's a very big question because if ice king is gollem, Simon is smegol and the crown is the ring then who is the sauron?
Let's look at what we know
- it gives the wearer control over ice
- Simon found it in Norway
- only the strong willed can control it without it controlling them
My hypothosis is that it was created by and/or for a norce tyrant who saut cryokeneces (control of ice)