contrary, why other rulers became willing, during thelast millennium of
Antiquity, to abdicate politicalcontroland switch over tofixed and immutable
calendar schemes.
The decisive turning point,Ishallargue, was the rise oflarge-scale empires
in the Near East during thefirst millennium BCE—Assyrian, Babylonian,
Persian—later to be followed by theHellenistic and Roman Empires. The
Persian Achaemenids, in particular, accumulated in a short period of time,
during the third quarter of the sixth centuryBCE, an unprecedented territorial
empire stretching from the western shores of Asia Minor to Egypt, theIndus
river, and the centralAsian territories of Transoxania: for thefirst time, nearly
allthe major western civilizations of Antiquity were brought under a single
geopoliticalentity. The rise of the great empires had, besides other implica-
tions for ancient history, the effect of promoting the spread offixed calendars,
partly (but not only) because they were more suited to the administration of
far-flung imperialterritories. The geopoliticalprocesses and the calendar
changes that went with them were complex and multi-directional, and
Ishallnot attempt to summarize them at this stage (for a grand summary,
readers are referred to theConclusion). For now, it suffices to remark that the
history and development of ancient calendars reflected the politicaland
administrative structures of the empires, kingdoms, and cities that used
them and sustained them.
A shift fromflexibletofixed calendar was studied already in my earlier work
on the Jewish calendar (Stern 200 1 ), whereIobserved a tendency in the Jewish
lunar calendars oflate Antiquity to abandon empiricalmethods (such as new
moon observations) and adopt insteadfixed calendar schemes. Much atten-
tion was given in this earlier work to the possible causes of this change. But my
awareness that a similar process had affected other calendars in Antiquity
subsequentlyled me to consider the history of ancient calendars as a whole.^4
Then, as the present project progressed,Ibegan to develop a different per-
spective on the Jewish calendar and to understand its development as a
general, rather than particular, historicalprocess. Thus in my earlier work
Iargued that the rabbinic calendar was graduallyfixed, between the third and
eighth centuries, because of the increasing geographicaldispersion of the
rabbinic movement (it had expanded, by the beginning of this period, from
Palestine to Babylonia) and the perceived necessity of rabbinic communities to
observe the festivals at the same time; afixed, predictablecalendar was the
only way of ensuring that the same dates between them were observed (Stern
2001 :2 11 – 5 6). But in this present work, thefixation of the rabbinic calendar
willbe viewed very differently as part of a macro-historicalphenomenon, the
same that affected allancient calendars and was related to the development,
(^4) This is already evident in Stern (2000a), whereIapplied to the Babylonian calendar some of
the ideas developed in the context of the rabbinic calendar in Stern (200 1 ).
4 Calendars in Antiquity