The codification of the Jerusalem Talmud at the end of the 4th century CE marked decisively the decline of Jewish life in the Land of Israel, which had begun with the destruction of the Second Temple in the year 70. From the 5th through the 11th centuries, Babylonia would be the demographic, religious, and intellectual center of Jewish life; the Babylonian Talmud (likely completed in the 6th century) would reign supreme; and the g’onim (heads of rabbinic academies) would be held up as religious authorities across the Jewish world. Yet Jewish life continued in what was then the Byzantine province of Palestine, as Tamar Marvin writes:
The Roman administration of the Land of Israel at first recognized officially the nasi, the continuation of the office of the head of the Sanhedrin (Jewish supreme court of 70), which went back to Second Temple times. In the early 5th century, when the “last nasi” Rabban Gamliel VI was accused of abrogating the types of laws [that both protected Jews and maintained their inferior status], recognition and Roman protection of the n’siut, or patriarchate, was withdrawn. The historical record is poor for the next several centuries, . . . but it seems that a yeshiva functioned in Tiberias in northern Israel.
Sometime after that, the title of the person at the yeshiva’s helm settled at ga’on, just like his colleagues in Babylonia, now Iraq. However, the ga’on of the academy of the Land of Israel combined the roles of two separate offices that existed in Babylonia, that of the spiritual leader and exilarch, [or lay leader]. In other words, he was a political representative to the government after the Muslim conquests as well as the leader of the yeshiva.
An additional form of leadership that developed during this early medieval period in Eretz Yisrael was the spiritual leadership of composing poetic prayers (piyyut), many of which remain with us and on our lips to the present day. Written in dense, exceedingly difficult Hebrew dotted with neologisms . . . and drawing upon Midrashic language, piyyut is hauntingly beautiful and tricky to navigate. The later poets of medieval Spain would largely eschew [this style] for what they considered purer and clearer biblical idiom, but the classical poets’ language remains breathtaking and unique.