The Elder Scrolls V is set in the lands of Skyrim
We don't know this for sure. This is only rumor.
where the nords basically came from;
The Nords are originally from Atmora, which is north of Skyrim. Skyrim is only where they settled in Tamriel.
Its supposed to be one of the first places that settlements began
There were already many settlements all over Tamriel, most of them being of Elven origin and some Nedic. Skyrim was only the first united kingdom of Men.
As for your question, I'm about 99.999% sure there will be at least
some new creatures in TESV, wherever it may take place. It will probably be a mix of some new and some old creatures.
We tend to keep all speculation related to TESV in http://www.gamesas.com/bgsforums/index.php?showtopic=1060989 and http://www.gamesas.com/bgsforums/index.php?showtopic=1060496 is used for ideas related to TESV.
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