Nope. In Norse mythology, he's the son of... Thrym and another Jotun. He isn't a frost giant, but he is adopted. The comics got a few things right, but screwed up a lot. Mjollnir isn't as heavy as they say it is, Jotun and Nifel Jotun (giants and frost giants) are two different things, and Nifelheim holds frost giants, not Jotunheim.
Beleive me , my ex was a marvel junkie and we had the idea to collaborate the two meeting at some point. Needless to say, I proved to her Norse Thor is better
I stand corrected, good sir.
Traits and flaws... are acceptable. No more than two traits/flaws combined. Be sure to play them.
The Background system seems to be based on building characters of a higher level than 1, so I don't think it's necessary. However, I can easily rule you've been at sea for [1d6=4] four months and know what you're up to. You might want to reflect that with Profession(sailor), Profession(navigator), or if you've been working the ballistae Profession(artilleryman) in place of your Craft skill, though.
Now, since you requested Background...
The Storm CoastThe Storm Coast is the collective name for a series of city-states and minor realms on the coast of the Gulf of Storms, some more notable members of which include the Noble Republic of Ligoria, Duchies of Vasir, Galam and Malchor, Archibishopric of Moun and the Republic of Groan. On the western coast of the Gulf is the Mirish Coast, home to the former Mirish states of Brighthall, Lonemine, Preston and the Archbishopric of Suul. Far south of those are the Bay of Korlan, the Ashen Coast and the Plaguelands. On the eastern coast, the Kingdom of Grune (or the Green Kingdom, to many) controls much of the coastline, while south of them can be found the Samakhet isles on the very edge of the Gulf of Storms.
The Storm Coast is well-named, and shipping can be treacherous, but the very storms that shake the sea make the coast (especially the northern coast) unusually lush and fertile, leading to not only wealth but the level of cultural diversity that keeps those city-states separate. Goods make their way to the Coast even from as far distant as Windheath or the Golden Reaches, on the far side of the world. It is a place where a fine merchant can make vast wealth - and a fine pirate can steal it. The number of city states also make it a jurisdictional nightmare - whichever state can field enough ships can control enough of its home waters, but there is no real dominant naval power.