It’s likely that much of the accomplishments of the more ancient world, in the middle east, was actually the result of the Jews who had been exiled and permeated great areas.
The greatest mistake that Spain ever made was expelling the Jews in 1492. The Jews were the basis of the mercantile operation in Spain. With their departure Spain depended on the gold taken from Latin America. When that dried up with the Latin American revolutions the Spaniards were left with little. 1492 in a sense was the beginning of the end for Spain.