Anno mundi

Anno Mundi (Latin for "in the year of the world"; Hebrew: לבריאת העולם‎, "from the creation of the world"), abbreviated as AM or A.M., or Year After Creation, is a calendar era based on the biblical accounts of the creation of the world and subsequent history. Two such calendar eras have seen notable use historically:

While differences in biblical interpretation or in calculation methodology can produce some differences in the creation date, most results fall relatively close to one of these two dominant models. The primary reason for the disparity seems to lie in which underlying Biblical text is chosen (roughly 5500 BC based on the Greek Septuagint text, about 3750 BC based on the Hebrew Masoretic text). Most of the 1,732-year difference resides in numerical discrepancies in the genealogies of the two versions of the Book of Genesis. Patriarchs from Adam to Terah, the father of Abraham, are said to be older by as much as 100 years or more when they begat their named son in the Greek Septuagint than they were in the Latin Vulgate (Genesis 5; Genesis 11) or the Hebrew Tanakh (Gen 5; Gen 11). The net difference between the two major genealogies of Genesis is 1466 years (ignoring the "second year after the flood" ambiguity), 85% of the total difference. (See Dating creation.)

During the Talmudic era, from the 1st to the 10th centuries AD, the center of the Jewish world was in the Middle East, primarily in the Talmudic Academies of Iraq and the Land of Israel. Jews in these regions used Seleucid Era dating (also known as the "Anno Graecorum (AG)" or the "Era of Contracts") as the primary method for calculating the calendar year. For example, the writings of Josephus and the Books of the Maccabees used Seleucid Era dating exclusively, and the Talmud tractate Avodah Zarah states:

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