determined not by scientific progress, but in most cases, by politicalfactors
and politicaldecisions.
The roleofpoliticalrulers in the design, development, and management of
ancient calendars was, indeed, paramount.Calendars gave rulers and politi-
cians the means of regulating economic activity, state administration, religious
cult, and in some contexts, their own politicaltenures; it is for this reason,
presumably, that most ancient calendars were controlled and set by political
rulers. Even in Mesopotamia, where the months and years of the Babylonian
calendar were determined infirst instance by astrologers (whose function as
courtiers or templeofficials had a politicaldimension in its own right),
questions about the beginning of the new month and the intercalation were
regularly referred to the king, in whose hands the ultimate decision always
rested (Chapter 2).When kingdoms and cities broke off from the Seleucid
Empire, accordingly, their kings and rulers retained the Babylonian calendar
but began reckoning it in their own, divergent ways (Chapter 5 ). For similar
reasons, but in very different ways, the persistence oflunar calendars in parts
of the Roman Empire where the Julian calendar had become dominant (Gaul,
Italy, and the Jewish andChristianDiasporas) may be interpreted as an
expression of dissidence (Chapter 6).Inallancient societies, controlof the
calendar was thus a way of asserting both political power and political
dissidence.
In this book,Ihave argued that the common, macro-historicaltrajectory
that characterizes the development of calendars from the mid-first millennium
BCEto thelater Roman period was essentiallyapoliticalphenomenon.It was
directlyrelated to the major socio-politicalchanges that transformed the
ancient world during this period, in particular, the rise of the great empires.
The Achaemenid, Seleucid,Parthian, Roman, and Sasanian Empires that took
over and ruled most of the civilized world within the geographicaland
historicalscope of this study encompassed very extensive territories which,
withlimited means of communication, were difficult to administrate and
control.Acalendar based on unpredictable, empiricalsightings of the new
moon and on irregular intercalations could not have been diffused and
reckoned uniformly across suchlarge territories. The emergence of these
large geopoliticalconfigurations during thefirst millenniumBCEwas condu-
cive, therefore, to the adoption offixed and predictablecalendar schemes.
But the adoption of fixed and standard calendar schemes in thelarge
empires was not merely a matter of administrative convenience; it also served
imperialideologicalpurposes. Thus the Achaemenid appropriation of the
36 5-day Egyptian calendar in the form of a newPersianZoroastrian calendar
that was widely diffused in the northern and eastern satrapies of the Empire is
likely to have been intended as a propagandist display of the Achaemenid
conquest and annexation of Egypt in thelate sixth centuryBCE, and similar
motivations may have been at play in JuliusCaesar’scalendar reform of 46BCE
428 Calendars in Antiquity