Continuing with a manuscript of mine:
There still existed a large Jewish colony in Mesopotamia, in the area to which the Jews had been carried off during the so-called “Babylonian captivity.” As already mentioned, the captives had prospered there, and most of them had chosen to remain in comfortable exile even when the road to return was entirely open. They enjoyed a flourishing intellectual life and maintained relatively close contact with their fellow-believers in and around Palestine. Soon, the Mishnah reached them there. But the rabbis didn’t, at first, occupy the first rank among Babylonian Jewry. Surprisingly enough, these exiles enjoyed a kind of quasi-political autonomy later than the Jews of Palestine did. For a time, their leader, who was known as the “exilarch,” functioned as a kind of prince—he claimed to be descended from the very King Zedekiah who had been carried away into captivity just after Lehi’s departure from Jerusalem in the sixth century B.C.—and served as a high official in the Parthian state that ruled the area. However, when the fervidly Zoroastrian Sasanian Dynasty came to power early in the third century, the privileged role and the political powers of the exilarch were curtailed. But as the political elite of Babylonian Jewry lost power and prestige, the influence of the rabbis expanded to fill the vacuum. Thus, eventually, just as in Palestine, the scholars took over. Jesus’ words, spoken more than two centuries before, were now truer than ever: “The scribes and the Pharisees,” he had said, “sit in Moses’ seat.”
 Matthew 23:2.