Three answers - accept any or all of them as you like
because I think they are all correct.
(1) It doesn't matter. What matters is what he taught.
(2) Probably not, going by http://en.wikipedia.org/wiki/Scythians
- but 'Scythian' is so poorly defined anyway that the answer is not going to be very meaningful.
(3) If you said which scholars and where, we might be able to give you a more reasoned response to their claims.