Right panchangam to be followed in the foreign countries

[Raghav K]

Respected scholars,

Many people live in lands other than what we call "India" today while most of our dharma shastras have been enjoined for bhArata bhUmi with some of them even delineating the specific boundaries of the tract of the land for which these principles apply. However, in the Itihasas and the Puranas we do read of sages as well as kings often visiting from foreign countries and continents for attending yagams or Vedic discussions/conferences such as the discourse on Bhagavatam, or the ashwamedha yajna conducted by Dasaratha. This means, they should have followed something in their respective countries as well. So, my question is, were they different dharma shastras for those lands back then? Are they lost now? 

It is not clear to me what is Bharata varsha as varied accounts have been provided across literature as to what is BhArata. We are told it was the land ruled by Bharata. We are also told it was called IlAvruta varsha previously. We are told the entire earth was ruled by Ikshvakus and Pruthu Maharaja because of which it is called Pruthvi. We are told the point at which the sons of Sagara divided land, the Sagaras we see today are formed and prior to this, the entire land was one. So, my questions now are -- today we call some of these continents as krauncha dweepa, etc. (e.g., United States). All priests here say "krauncha dweepe, ramanaka/ramyaka varshe, aindra khande, etc" However, the descriptions of these dweepas, varshas, or khandas per Vishnu/Bhagavata and other Puranas with the respective oceans surrounding them do not match what we see today. Not sure who is the origin of this mordern-day mapping and how they came into being. Also, most scholars have used things such as samaya nirnaya pattika etc to calculate/extrapolate their calculated panchangams to these foreign lands today. Accordingly, we see some tithis/nakshatras/festivals coming a day prior to they occurring in what we call India today. However, there are others who believe only India's panchangam is to be followed in foreign lands too. Which of these arguments are correct? While there are some who believe leaving the country is the worst of sins worth needing a prAyaschittam, there are others, even saints traveling across the oceans to preach. While some have argued these lands not karma/yaga bhumis, they are only bhoga bhumis, are contaminated with cow-killing and unholy sexual relationships, today, India consistently ranks #1 or #2 in cow-killing and is one of the biggest exporter of beef to the rest of the world, let alone other sins described. We are told that runa with land, spouse, etc are coming from previous births and karmic. So, if, say, one's karma has put one in these foreign lands, and one is still dharmic and wants to follow everything sincerely, what tithi/sankalpas/panchangams are applicable? Is living in foreign lands really a sin or all such nindAs arthavadas or later-day interpolations? The Vedic blessings still read "pruthvi sasya-shAlini, lokAh samastAs sukhino bhavantu, although specifically calling out deso'yam kShobha rahitaH" There are many scholars in this group who are also well-versed with these aspects. Would be grateful if you could share your insights and perspectives on these topics which are very much relevant for modern day society and all future generations.

Thanks and warm regards,

Raghav