The Nitei Gavriel Pesach 2 Chapter 43:9 brings in the name of the Shevet Halevi that since a convert is as if he is newly born there is a question whether he is still considered a Bechor. Therefore the Nitei Gavriel concludes that it is best that he should either make a Siyum or be part of a Seudas Mitzva.
According to this article, most Poskim do allow one to brush one's teeth on the three minor fasts, especially if they are going to be in some level of discomfort.
..While the Kaf Hachaim (OC 567:13) forbids rinsing even with less than a revi’is, most poskim are more lenient, especially when one is uncomfortable. Thus, the Rema (Darchei Moshe OC 567:2), ...
The Rama rules in OC 558 that the prohibitions on wine and meat remain in force for only the night of 11 Av. The Mishna Berura (sk 4) notes that this is meant to be specific, and the other prohibitions do not apply immediately following the fast.
The Talmud (Pesachim 54b) states that only for Tisha bAv must we be stringent for Bein Hashemashot. There is an opinion in Rishonim that only regarding the Bein Hashemashot at the beginning of the day is Tisha bAv unique, but all fasts require being stringent at the end because we have to wait until it is certainly night to uproot the current status (chazaka)...
Alshich (to 5:5-8) says that indeed she didn't eat at the first feast. Among many other things, this explains why the first one is just described as "the party which Esther made" (5:5), while to the second one Achashverosh and Haman came "to drink with Queen Esther" (7:1).
Note 10 in Rav Eliezer Melamed's article on the "lighter fasts" states as follows:
וכיום ההוראה הרווחת לנשים אשכנזיות שלא לצום. ועיין בפסקי תשובות תקנ,
א, שהביא דעות מופלגות להיתר, שכל הנשים הראויות לילד פטורות מהצום, כדי
שיהיה להן כוח לילד. ויש אמרו שתפדה את הצום בצדקה. ע"כ. ואין נוהגים
להורות כמותם, אבל במקום ספק אפשר לצרף את דבריהם להיתר.
You can listen to him discuss it here at 56:12. He says it isn't rau'i l'achilat adam (fit for human consumption) so it isn't considered eating. He quotes some opinions that it is a problem of washing the inside of the mouth on Yom Kippur, but he doesn't seem so impressed by the idea.
These fasts are counting from Nisan as the first month (the Jewish religious calendar).
The fast of the 4th month is 17 Tammuz.
The fast of the 5th month is 9 Av.
Here, the fast of the 7th month is Tzom Gedalia (usually observed on 3 Tishrei) although Yom Kippur also falls in the 7th month.
The fast of the 10th month is 10 Tevet.
These fasts commemorate ...
Fast days are not optional. The "minor" means that they start at daybreak rather than the night before (as do tish'a b'av and yom kippur). Note the rules quoted below for when one may skip the fast (because of illness).
Yom Kippur is required by the Torah and Ta'anis Esther is connected to Purim not the destruction of the temple. Once the temple will have ...
Only Yom Kippur and Tisha b'Av are 25-hour fasts. The others are minor fasts, from dawn (first light, before sunrise) until nightfall (full dark). The minor fasts are:
Fast of Gedaliah (3 Tishrei)
Fast of Esther (13 Adar)
Fast of the Firstborn (for those to whom it applies) (14 Nisan)
You can read more about these fasts at Judaism 101.
About the second part of the question: Yalkut Shimoni (to Esther 4:16) says that he limited the fast to those "found in Shushan" because they were the ones who had eaten at Achashverosh's feast. The Jews in the rest of the empire weren't guilty of that.
[That they too were in danger is attributed by R. Shimon bar Yochai (Megillah 12a) to their having bowed ...
The Vilna Gaon (OC 470, s.v. v'ein) explains the opinion that exempts women from fasting as due to the fact that women lack k'dushas b'choros (the sanctified status of firstborns). A male with an older sister also lacks k'dushas b'chor since he is not a firstborn, so the opinion that exempts the older sister would certainly exempt the brother.
In fact, a ...
The custom of reciting Avinu Malkeinu repetitively by the chazzan and congregation is brought in Mateh Efrayim (תרב סי"ג), without any explanation. [The Mateh Efrayim himself writes to begin from א"מ קרע, however the Ktzey Hamateh at the bottom brings the custom to start from א"מ החזירנו בתשובה]. The only reason I could find is mentioned in שער יששכר מאמר ...
The question of Kiddush on Yom Kippur is discussed first in the Gemara Eiruvin
The Shibolei Haleket (312) writes that because one does not normally eat on Yom Kippur, the Sages never required mention of the holiday in kiddush or even bentching. In fact, making Kiddush would be improper because one might see kiddush being made and think that it should be ...
The simple answer is two-fold:
The Jews already knew that the decree had occurred, and they were quite upset about ("v'hair shushan navocha"). You can imagine they were paying attention to the local news.
Mordechai was the head of the Sanhedrin, in addition to being a figure in the king's court, both very visible positions. Given (1), people were probably ...
Yom HaShoah falls on the 27th of Nissan. It is forbbiden to fast during the month of Nissan (Shulchan Aruch OC 429:2). I've never met anyone who fasts on that day, and I would question anyone who does.
There are a variety of things that people do on Tisha B'Av. Many people spend most of the morning reading and discussing the Kinnos. It is also permitted and widespread to learn certain bits of Torah that are relevant to Tisha B'Av. These include Eicha, Iyov, the story of the destruction of the Temple which is related in Gittin 56b-58a and Sanhedrin 104, the ...
The Chassam Soffer in Toras Moshe mahadurei kama in his drush for 7th of Adar d.h. kasuv addresses this. In short he says that just like every generation that the Beis Hamikdosh is not rebuilt is as if it was destroyed, so too every year on the tenth of Teives which was the beginning of the destruction, we are judged and a gezeira is put forth if the Beis ...
The Rema is referring to the sefer Tanya Rabbasi, who writes (siman 34):
שבראש חדש אף על פי שאסור להתענות...
In general, when sifrei halachah quote "sefer tanya", they are referring to the above sefer.
R Eli Mansour explains here
During the times of the Beth Hamikdash, those who were unable to bring
their sacrifices on the day of Shavuot itself – which in Israel is
celebrated only on the sixth of Sivan - were allowed to do so during
the six days following Shavuot, through the twelfth of Sivan
As such some don't say Tahanun in the week after ...
The Kaf HaChaim writes here that you fulfilled your obligation if you accidentally says it as a stand-alone Beracha before Re'eh. Therefore:
1 - You do not say it again in Shema Koleinu.
2 - It was not a Beracha in vain.
The Machon Yerushalayim edition of the teshuvos, which is available on Otzar Chochmah, has a footnote that asks your question and suggests "the author of the Shulchan Aruch" was added by mistake at some point.
ואולי הוכנסו תיבות "ובעל שלחן ערוך" בטעות בתוך התשובה, כי רבינו נפטר לפני לידת בעל שלחן ערוך. וצ"ע.
Because of the safek discussed by the Shevet HaLevi, Rav Elyashiv shlit"a recommends "that these bechorim participate in a seudas mitzvah." (http://torah.org/advanced/weekly-halacha/5758/pesach.html; Harav Y.S. Elyashiv - Seder ha-Aruch, vol. 3, pg. 44).
A friend of mine got married the day after Yom Kippur. At the end of Yom Kippur services, somebody showed him in the Chabad machzor the instructions that one shouldn't fast the day after Yom Kippur, with the exception of a Chatan who is getting married that day.
Rav Moshe Feinstein (Igrot Moshe OC 1:168) holds that in general one can have a wedding on the night of 17 Tammuz when necessary, but says in that same teshuva that for sure when the fast is Nidche that you can't have a wedding Saturday night. (I assume all other restrictions follow.)
The following does not answer the historical aspect of the question directly, but it provides background suggesting that (1.) the circumstances during the diaspora seem to have frequently (if not usually) qualified as "times of oppression", not only during the most acute tragedies of Jewish history, and (2.) the fasts under those circumstances would not have ...
The Mishnah Brurah (549:1) explains that the main point of a fast is to do teshuvah, and not the fast itself: By Ninveh, concerning G-d undoing the decree to destroy them, it says "And G-d saw their actions," not "And G-d saw their fast." The fast is merely a preparation for the teshuvah. He continues, quoting the Chayei Adam, that those people who spend the ...