instituting a new calendar and disseminating it across their empire; the
Zoroastrian priesthood less clearly so.^66 Zoroastrian priests had no good
reason to seek out and adopt a new calendar from Egypt, displacing whatever
cultic calendar had been used hitherto; Egypt was a distant civilization with
which Zoroastrian priests are not known to have had any contacts or cultural
affinity. The Achaemenid rulers, in contrast, would have discovered the
Egyptian calendar after Cambyses’conquest and annexation of Egypt. The
new calendar which they instituted would have been intended not only for
religious purposes—as the Zoroastrian nomenclature of months and days
suggests—but also—as the documentary evidence seems to indicate—for
political, administrative, and economic use.
The Achaemenid rulers, however, were not in any need of an official,
imperial calendar, as this function was already fulfilled by the Babylonian
calendar. It is becoming increasingly evident that the Babylonian calendar was
used by Persian officials in all periods and all parts of the Achaemenid Empire,
from Bactria in the east^67 to Lycia (Asia Minor) in the west^68 and Elephantine
in the south of Egypt.^69 The biblical books of Zechariah, Ezra, and Nehemiah
suggest its use in the province of Judaea, whilst Esther and Nehemiah suggest
its official use in Susa, Achaemenid capital of Elam—all in the early Achaeme-
nid period.^70 As we have seen in Chapter 2, individual Achaemenid kings
played an important part in determining how Babylonian intercalations were
made during their reigns; their interest in the Babylonian calendar was
undoubtedly related to its use as an official imperial calendar.
Nevertheless, the institution of the Persian Zoroastrian calendar appears to
have been an attempt—which may never have materialized as fully as
intended—to introduce a new and distinctively Persian, official imperial
calendar in parts of the Achaemenid Empire that had never been ruled by
Assyrians or Babylonians, and that had therefore no prior tradition of using
the Babylonian calendar. These regions, which in territorial terms constituted
maybe half the Empire, were marked out by the continuous mountain ranges
(^66) More recently Boyce (2005) 7 has conceded that the calendar must have been instituted by
Persians from the‘Treasury’together with‘astronomer-priests’, and that only the Achaemenid
rulers would have had the power and military resources to enforce and disseminate this new
calendar among the Zoroastrians in the Persian Empire.
(^67) Shaked (2004) 42–5, Naveh and Shaked (forthcoming). Babylonian month-names
were adopted in this period in Bactria as well as in Sogdiana: see above, near n. 47.
(^68) Dupont-Sommer (1979), Fried (2004) 140–54. In this trilingual inscription, the Lydian and
Greek texts are an appeal of the city of Xanthos to the satrap Pixotaros; the Aramaic text is his
offi 69 cial reply to them. Only the latter is dated,‘Siwan, year 1 of Artaxerxes’.
e.g. a letter in the Elephantine archive dating from 427 BCE, from the satrap Arsames to his
Persian officials Achaemenes and Bagadana (Porten and Yardeni 1986–99: i. 94–5 no. A6. 1);
also perhaps Arsames’letter of 411 BCE authorizing a boat repair (ibid. 96–101 no. A6. 2).
(^70) Judaea: Zech. 1: 7, 7: 1, Ezra 6: 15, Neh. 6: 15. Susa: Esther 2: 16, 3: 7, 3: 13, 8: 9, 12, 9: 1, Neh.
1: 1, 2: 1. These works are likely to have been composed in Judaea (perhaps still during the
Persian period), and thus represent reliable sources for calendar practice there.
186 Calendars in Antiquity