Hello Alan,
My best guess would be Jormungandr, the Midgard serpent.
But the knife doesn't look Finnish to me.
The Finnish puukko is quite simple, even the high end/dress pieces. Moreover, the typical puukko has no ricasso, with the edge going all the way to the hilt/ front bolster.
However, even for a Norwegian knife it is rather unusual due to its lavishly carved hilt and sheath. The style of the carving and decoration on the sheath also doesn't look very "Norse" to me. Special, less traditional order?!
But just my two cents...