I've heard many rumors that Satoshi Nakamoto is of Russian origin and that Bitcoin was created in Russia. Many online forums discuss this topic. What do you think?
There are so many people discussing this that I have never even heard of it. 
What online forums are you talking about? This is the main forum in the BTC-community, but I haven't seen any discussions like this here (except yours).
What are these assumptions based on? There must be direct or indirect facts that suggest that the creator of bitcoin Satoshi Nakamoto is from Russia.
A bit of speculation.
Even if this is true, does it really matter? What matters is what benefits bitcoin provides, not who created it and in what country.
Personally, I don't care about the origin of the creator of bitcoin. I appreciate his contribution that changed the world.