Ironically, the North-Germanic pagans didn't speak Old Norse. Instead
they spoke "mal wikinga":
http://www.geocities.com/Athens/Acropolis/1327/
(or Proto-Norse if we want to dig even deeper)

sihuarþaR

> Hinn 31. júlí 2003 lét Daniel Ryan Prohaska þetta frá sér fara:
> > I've heard "asatru" a couple of times recently. Can someone

explain to

> > me what exactly asatru is and what connection there is to Old

Norse?

>
> It's an Icelandic compound word from 'ása', genitive of 'æsir',
> and 'trú' which means "faith". Thus 'ásatrú' means "Æsir-faith".
> The word is often used to refer to North-Germanic paganism
> in general.
>
> The prime interest for many people in learning Old Norse is to
> be able to read such works as Snorra-Edda and Sæmundar-Edda which
> are the most important primary sources for Norse mythology.
>
> Kveðja,
> Haukur