from my understandign (I don't remember where I heard/read it - may be Kol Chai) that the killing of Gedalya led to the complete expulsion of all Jews in Israel and not even one was left. Also the land of Israel became comletely desolate with not even a bird flying over the land. So it was like the final blow of the churban and the finalization of the galut

my father always asked - "Would Gedalya fast for me?"

I think it's really an excuse to take a break from eating after the food marathon on chag.

Read the narrative around it and the answer becomes clear.
Although we are taught repeatedly about how evil Nevuchadnezzar and Nevuzaradan were when it came to destroying Yerushalayim, the book of Yirmiyahu implies that they were gracious in victory.
Having exiled the bulk of the population, the remnants were granted autonomy under Gedaliah, the Jewish governor of the region. What's more, the community was starting to grow and rebuild despite the tragedy that had been visited upon it.
Remember as well that Gedalyah's assassins were working for the local Ammonites who didn't want a Jewish state to reappear.
The fast is for the loss of potential. Has Gedalyah survived, the Jewish community would have been in much better shape when Ezra and Nechemiah returned. Instead, they found all sorts of troubles because the land had been yudenrein for decades.
When we see the Neturei Karta going to Iran and Peace Now activists making common cause with holocaust denies (eg. Mahmood Abbas), we see that the lessons of the fast were never learned.

Rafi what is your source that נבוכדנצר tossed the remaining Jews out?

it was really from memory, but I just did a search and according to both this page: http://www.torah.org/learning/yomtov/yomkippur/vol1no39.html# and the fast of gedaliah wiki page, the remaining jews ran away out of fear of retribution by Nebuchadnezzar.

thanks Garnel. Very well put.

Why fast for a Babylonian puppet? I don't get Jews at all.

I heard a different twist that may answer your question.

The assinator was a Jew. He should have been doing Teshuva on Rosh Hashanah. Maybe he did. But the next day, he commits a heinous murder.

We are fasting today to make sure that does not happen to us. We need to drive home the lessons of RH and not fall prey to aveira relapse once RH ends.

Or a patriot who hated a Jew being subservient to the Babylonian king. There's more than one way of looking at it. Gedaliah served a hated enemy who conquered Jerusalem and destroyed the Temple.

we fast on tzom gedaliah for the same reason that we celebrate on yom ha'atzmaut.Brad

Rav Soloveitchik in Haarerei kedem 2:155 explains beautifully that the last hopes for the immediate rebuilding of the Beis Hamikdash were extinguished together with Gedalia

Norman, Yishmael was no more a patriot than the neturei karta are. It is silly to suggest that his motives were as you propose.

It is well known that the spiritual levels of the Jews during the time of the 1st Bais Hamikdash were some of the loftiest in our history. The 2nd one, and the people in its time, great as it and they were, did not compare.

Gedalia was the last remnant of the people of that time, our last living connection to the 1st Bais Hamikdah and those levels. It was a zechut to the people living after its destruction to still be able to point to a G d fearing individual that lived during that time. A living artifact.

What's the big deal about artifacts? Of the Bais HaMikdash or ancient Jerusalem? Why do people revel in going to the Kotel? It gives us a connection. Here we are thousands of years later, surviving and thriving and I can still connect with that ancient time of the Jewish people, pray where they did and feel a closeness to G d that I am not able to anywhere else.

People cling to tangible memories of previous precious times or people. Eg. "This bracelet is special to me because my grandmother, A"H, gave it to me."

Similarly we can cling to people who lived in a previous generation. Here in RBS, there is sometimes a lecture given by a grandson of the famed Chofetz Chaim. It's a way to connect to a sage of that caliber. "You mean you actually KNEW him and learned with him?"

Gedalia was the Jews' last connection to the holiness of the Temple and the period it stood in. It was comforting and inspiring to be able to point to someone and say, "He was THERE!"
When he was killed, we lost our last living connection to the 1st Bais HaMikdash and what that period represented.

That is why we fast.

Wanna Sab is wrong.

Yoma 9b tells us that the first Temple was destroyed because the people engaged in "idolatry, immorality, and bloodshed" but the people of the second Temple "busied themselves with Torah, doing mitzvot, and giving charity."

Yoma 9b has to conclude that sinat chinam caused churban bayit sheini.

Now... why do we fast on Tzom Gedaliya?

Rambam, Sefer Hamitzvot, Positive Commandment #153

"The Blessed One commanded us to sanctify the months and to calculate the months and the years. This is the mitzva of sanctifying the months. This is what God said: "This month shall be to you the beginning of months" (Shemot 12:2) … But this mitzva can only be performed by the High Court, and only in the land of Israel. For this reason, sanctifying the months on the basis of testimony is suspended today because there is no High Court..."

"... I will add an explanation for you: Were it possible, for example, that there would be no Jews living in Eretz Israel (far be it from God to do this, for He promised that the remnants of the people would never be entirely uprooted), and there would be no court there, and there would be no court outside of Israel that had been ordained in Israel, our calculations would not help us in any way whatsoever, for outside of Israel we are only authorized to make the computations, intercalate the years, and fix the months, in accordance with the conditions mentioned, as we have explained. "For the Torah will go forth from Zion, and the word of God from Jerusalem."

- Rambam, Sefer HaMitzvot, Positive Commandment #153

Joshua, it's true that the 1st Bais HaMikdash was destroyed by those 3 grave sins, but overall the period it stood, under the rule of Shlomo Hamelech at least, was on a greater level than the 2nd one.

I don't understand how your explanation about declaring Rosh Chodesh answers the question of why we fast for Gedalia.