Calendar disruption is also evident when calendars of different cities are
correlated in epigraphic sources. Double dates reveal that the months of
different cities were not consistently related to one another: for example, the
Thessalian month of Thyos corresponded inc.161/0BCEto the Delphic month
Endyspoitropios, but inc.124BCEto the Delphic month Bysios. Inasmuch as
the Delphic Endyspoitropios and Bysios are two months apart, this inconsis-
tency was presumably the result of irregular or arbitrary intercalation, in
one—or both—of these calendars.^36
The relation between days of the months of different cities was also partic-
ularly erratic. Aristoxenus (late fourth centuryBCE) remarks, though only by
way of example, that‘...the 10th of the month at Corinth is the 5th at Athens
and the 8th somewhere else’.^37 But more concrete evidence is available from
other literary sources. Documents cited by Thucydides suggest that in
the spring of 423BCEthe date of 14 Elaphebolion at Athens corresponded to
12 Geraistios at Sparta; whilst in 421BC, 25 Elaphebolion at Athens corre-
sponded to 27 Artemisios (which probably preceded Geraistios) at Sparta.^38
Ps-Themistocles (Epistles 7 —date uncertain) refers to a last day of Boedro-
mion (at Athens) that corresponded to 10 Panemos (at Corinth). Plutarch
(Life of Aristides, 19. 8–9) reports that the battle of Plataea (479BCE) was on 4
Boedromion in the Athenian calendar, and 27 Panemos in the Boeotian; he
goes on to remark about the diversity of civil calendars.^39 Epigraphic evidence
is available in Crete, where the 20th at Knossos once corresponded to the 4th
in Gortyna.^40
however, is yet to be supported with evidence; and even if true, it would have been difficult to
conform to this rule in practice, since intercalations were often required for religious or other
reasons (see}5 below).
(^36) Bickerman (1968) 31, Hannah (2005) 81–2. But inconsistencies within a margin of one
month, such as between the Athenian and Delian calendars (see Hannah 2005: 73–7), are
not necessarily indicative of irregularity: they could easily have arisen if Athens and Delos were
using regular but different systems of intercalation.
(^37) Aristoxenus,Harmonica2. 37 (Macran 1902: 192). Pritchett (1947: 239–40, 243) rightly
remarks that there is no indication, in this passage, that these discrepancies were exceptional. 38
Thucydides 4. 118. 12 (423BCEAthens), 119. 1 (423BCESparta), 5. 19. 1 (421BCE). The
correspondence of Elaphebolion with different Spartan months in 423 and in 421 suggests that
different intercalation(s) of months were made in each city. Attempts by Gomme (1945–81) iii.
713 – 15 to explain why Athens was two days ahead of Sparta in 423, but then two days behind in
421, are completely speculative and futile (see Dunn 1998: 219). Pritchett (1947) 238–9 questions
whether the dates given by Thucydides for Athens and Sparta in 423BCErefer in fact to the
same day, as Sparta may have sworn the truce a little later; see also Samuel (1972) 93.
(^39) Pritchett (1947) 238–40, Samuel (1972) 68 and n. 1, Dunn (1998) 219–20. On the sources
Plutarch would have used for his datings, see Grafton and Swerdlow (1988) 26–7. As to his
comment on calendrical diversity, Plutarch seems to be referring also to his own period (late 1st–
early 2nd c.CE); however, in this period the diversity of Greek and Macedonian calendars would
have been due to very different factors, namely the transformation of the latter into solar, Julian-
type calendars (on which see Ch. 5). 40
Bickerman (1968) 33 (and generally 32–3), citingIGxii/3. 254.
34 Calendars in Antiquity