this kind—thefixation of the Saros Canon cycle—to the advent of Seleucid
rule, after Alexander the Great’s conquest in the late fourth centuryBCE.
Why the Saros Canon cycle would have becomefixed under the Seleucids is
only a matter of speculation. It is unlikely to have been related to Hellenization
or Hellenistic culture, for the Greek calendars (and presumably also the
Macedonian) were traditionally far moreflexible and erratic than their Baby-
lonian counterpart (as we have seen in Chapter 1). It is possible, instead, that
the Seleucid kings, although bearers of the title‘king of Babylon’, did not
consider themselves, as Greeks, sufficiently Babylonian to dictate how the
Babylonian calendar should be reckoned. They may have been reluctant, for
that reason, to deviate from the Saros Canon cycle that had become estab-
lished in Babylon under Achaemenid rule.^117
Intercalation in the Parthian periodIt is commonly assumed that the Babylonian calendar and its cycle of inter-
calations remainedfixed for ever through the whole of the Parthian period,
and possibly even after the fall of the Parthians in 224CE.^118 This assumption,
however, is impossible to prove, because intercalations are even less well
documented in the Parthian period than in the last decades of Seleucid rule,
as shown in Table 2.6(a). The Saros Canon cycle is reasonably well attested in
thefirst twenty years of Parthian rule (142/1–123/2BCE), though not without a
conflict of evidence in 125/4; after that, the record becomes very sporadic. The
few sporadic intercalations that are later attested do match the Saros Canon
cycle (Assar 2003); but in the absence of continuous sequences, they cannot
prove that the Saros Canon cycle was consistently followed. The conflict of
evidence in 125/4 (which previous scholars appear not to have noticed) may
be interpreted, in fact, as the beginning of a breakdown of the Saros Canon
cycle in thefirst decades of Parthian rule; although it may also be taken as an
irregularity similar to those attested already in the Seleucid period (in the 380s
and in 266/5). Astronomical sources such as the Diaries (which date until the
mid-first centuryBCE) suggest that during the early Parthian period the
Babylonian calendar was stable in relation to the stars and solar year, which
suggests at least that intercalations were well regulated;^119 but this could have
been achieved without afixed 19-year cycle. Given that the Saros Canon cycle
(^117) In this section and the next, I am only concerned with how the Babylonian calendar was
reckoned in the Seleucid and Parthian periods. TheMacedoniancalendar of the Seleucid and
Parthian rulers—in principle, but not necessarily in practice, assimilated to the Babylonian
calendar—will be discussed in Ch. 5.
(^118) As assumed e.g. by Parker and Dubberstein (1956), Stern (2004).
(^119) The texts in Sachs and Hunger (1988–2006), however, are often restored and dated on the
assumption of the Saros Canon cycle, which can lead in some cases to a circular argument.
114 Calendars in Antiquity