Megillat Taanit

In the Mishna, Megillat Ta'anit is sometimes referred to by the name "Megillah" alone, and the name "Megillat HaHasmonaim" - the Scroll of the Hasmoneans - is also found.
Contrary to what one would expect from the title, it contains dates and festivals on which it is forbidden to fast, and on some of these it is even forbidden to eulogize the dead, as the festivals are for the entire Jewish people; all this, while in the basic text of the there is no explantion or historical connection.
There is no proof as to when it was written, but there are grounds for the assumption that the basis was written between 34 B.C.E. and 71 A.D. and there is a late midrashic statement claiming that the "Scroll on Fasting" already existed at the time of the Persian Empire as, according to this midrash, when Queen Esther requested that the Jews fast for three days before she appeared before the king, Mordechai argued with her, that these same days are recorded in the Megillat Taanit as days on which it is forbidden to fast.

The Megillat Taanit may be divided into two parts, the basis of which is written in Aramaic, with explanatory notes in Hebrew. It may be said that the relationship between the two is similar to that between the Mishnah and the Talmud; however the situation here is reversed, and the Mishnah is entirely in Hebrew, while explanatory notes of the Talmud are mainly in Aramaic.
As to the question of when the explanatory notes were written, there is difference of opinion. Some say it was after the period of the Amorai'im - The Talmudic Sages - that is, after the completion of the two versions of the Talmud: in which case the text of the explanatory notes will be of no assistance in dating the Megillat Taanit itself. For example, we find in the text that it is forbidden to fast on the 28th of Adar, "as on this date royal decrees were cancelled". These cannot be the decrees of Hadrian after the fall of Betar approximately seventy years after the destruction of the Second Temple, yet it is feasible that the reference is to the decrees of Antiochus.
In the Megillat Taanit some Bible dates are mentioned on which it is forbidden to fast or deliver an eulogy - the second day of Pesach, for instance, which is determined in the Torah as a sacrificial festival; as well as the days of Purim, 14th and 15th of Adar. In the explanatory notes, the words of Rabbi Yehoshua ben Korchah are quoted. He equates the festival of Purim with that of Pesach, and by drawing a more important law from one of lesser importance, states: "On Pesach the Egyptians decree to kill the male children was cancelled, and on Purim the decree to kill both male and female was cancelled......If it is forbidden to fast on Pesach because it is a festival day, then certainly it is forbidden to fast on Purim"....The Megillat Taanit is the only source for this explanation.
As there are other Biblical festivals when it is forbidden to fast which are not mentioned in Megillat Taanit, it could well be that the Megillat Taanit rectified the situation within the Jewish People by setting out the festivals subject to differences of opinion, or those which were not properly observed.
Most of the festivals mentioned in Megillat Ta'anit are associated with events during the Hasmonean dynasty, military and political victories, from the time of Yehuda ben-Mattityahu until Yochanan Horkanus, as verified in the Book of the Maccabees as well as in the writings of Josephus ("Yosef ben Mattityahu)".
Furthermore, there are differences of opinion regarding the date of annulment of the authority of the teachings in the Megillat Taanit. In his time, Rabbi Gamliel already could not find sufficient corroboration and diminished the authority of the Megillat Taanit.
It is possible that the annulment of the authority of the Megillat Taanit did not happen on a single occasion; but may have been a process that took place during the third century.
Still, despite differe