How Far Does חמר מדינה Extend?

Mar Yanuka and Mar Kashisha, sons of Rav Ḥisda, said to Rav Ashi: "Once Ameimar happened to our place and we did not have wine for havdalah. We brought him beer and he did not separate, and he passed the night fasting. The next day, we exerted ourselves and brought him wine, and he separated and tasted some. The next year, he again happened to our place. We did not have wine, we brought beer. He said: 'If so, it is the wine of the country.' He separated and tasted some.'"

A country whose alcohol is predominantly beer, even though it is invalid for kiddush, it is permissible to separate upon it, since it is the country's wine.

And further inquiry is necessary regarding if we can sanctify upon beer where it is the country's wine, such as when we separate. And the whole passage that prohibits reciting sanctifying over beer we can say refers to a case where it is not the country's wine.

Know, that since Rav said, "Just as one does not sanctify, so, too, one does not separate." But, if it is the country's wine, it is obvious that we separate over it.

The conclusion of the matter is that we separate upon beer if it is the country's wine, but not upon bread.

And, according to Rabbenu Tam, we do not sanctify also over bread. But there is some doubt if we sanctify upon beer.

In a place in which wine is uncommon, one can sanctify over beer and other beverages, since wine is uncommon there, other beverages are that country's wine.

And Rabbi Samuel, son of Meir, (1085-1158) explained that beer is called a country's wine since wine is not in every city. And there are those who explain it as a country's wine is only if wine is beyond a day's distance in any direction. And, from Maimonides' words, it would seem that one does not sanctify upon it, that he wrote, "A country whose alcohol is predominantly beer, even though it is invalid for kiddush, it is permissible to separate upon it, since it is the country's wine."

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And my father wrote that we sanctify upon beer if it is the country's wine. And, nevertheless, it is better to sanctify over bread, since the meal is coming for honoring Shabbat, but it is better to sanctify over beer for the morning's meal, with the explanation being that one blesses shehakol nihiyeh bidvaro prior to the hamozi blessing, that, if one were to bless upon the bread first, there would be no difference.

"In a place where wine is uncommon, sanctify over beer..." - In the tenth chapter of Pesahim, they say that Rabin separated upon beer where it was the country's wine and we say after Rav Huna asks of Rav Hisda about sanctifying over beer and it is answered that one neither sanctifies over it nor separates upon it. And Rabbi Asher, son of Yehiel, wrote that even if we were to explain Rav Huna's question with a country's wine, it is possible that

And what our teacher (Rabbi Yaakov, son of Asher (1269-1343)) has written from the words of Maimonides "it appears" is because it is possible that Maimonides only differentiated between kiddush and havdallah for a country most of whose alcohol is beer even if they do have wine. But, in a place that is entirely wineless, we sanctify over beer.
However, since we do not find the Talmud differentiating on this matter, it would be more apparent that even when there is a wineless place, it says to not sanctify over beer.

One does not separate upon bread, but one may separate over beer if it is the country's wine. And similarly is the ruling for other beverages aside from water.

Rabbi Isserles' comment: And it is better to separate over a defective glass of wine than it is to do so over beer. And we are accustomed to separate on the departure of Passover upon beer rather than wine, since one is desirous upon it.
And a holiday that occurs upon the departure of Shabbat, in which there is a kiddush said over bread, there are those who say upon kiddush one can also separate over it together. And there are those who say that it is better to say both kiddush and havdallah over beer.
Rabbi Isserles' comment: And the first opinion is primary.

In a place where wine is uncommon, there are those who say we sanctify over beer as well as other beverages aside from water. And there are those who say we do not sanctify [upon those non-wine beverages].

But, according to Rabbi Asher ben Yehiel (1250 – 1327), on a Friday night, one should not sanctify over beer, but rather bread; and, in the morning, it is better to sanctify over beer that one would bless shehakol upon it prior to the blessing of hamozi., rather than blessing over the bread first, since there would be no difference there. And they are words of reason.

Rabbi Isserles' comment: And such is the common custom according to Rabbi Yehiel's words. And if there is wine in the town, one should not say sanctify over bread. And someone who doesn't drink wine on account of a vow, they should bless over the wine and the others sitting with them should drink; but if there aren't others with them, they should sanctify over bread and not wine; or that person can listen to others sanctify (and answer Amen).

A cup over which one would bless the birkat hamazon should only be done with wine rather than with any other beverages, even if one established one's meal upon them. And if wine is uncommon in that place but beer or other beverages are considered to be the country's wine, we do bless upon them, aside from water.

Rabbi Isserles' comment: And regarding those who are accustomed to bless upon beer in our countries, we shouldn't stop them, since there are those who say birkat hamazon does not require a cup at all. And furthermore, beer is the primary country's wine and people do establish meals upon it. And even if wine were to be found in a city, nevertheless, it is not called common for this matter, since it is expensive and it is not possible to buy it for each meal to bless upon it. Indeed, it is the choicest way to perform the mizvah to bless wine upon the birkat hamazon. And there

It is better to make kiddush on beer: but in a place where wine is common, one should certainly bless on wine even during the day. But, nevertheless, if wine is expensive, like in these regions, one should not be so meticulous going after wine, since it is not a full obligation like there is an obligation at night, and it is sufficient for that.

And for this reason, even the great rabbis in our regions are not accustomed to bless on wine during the day, and one who blesses upon wine also in the day, certainly does it in the choicest way, as is explained above.