We have already seen that the Medo-Persian kingdom succeededBabylon. It is clearly the kingdom here described. It was noted for cruelty and thirst of blood.
The ribs in its mouth may denote the union
of Media, Persia and Chaldea.
It subdued many and populous kingdoms. Ahasuerus, or Artaxerxes, reigned over one hundred and twenty-seven provinces."
James White