Among which historic people, given names were mostly ending with "ix" sufix? (like Asterix and Obelix)
There were no such people. The "ix" ending alludes to the "rix" suffix present in the names of Gaulish chieftains such as Vercingetorix or Ambiorix. However, the meaning of "rix" was "king", so no such suffix was ever present among the names of common folk.