The indication of the Julian date of the first month in each calendar is only an approximate guide. All of these calendars varied, some of them very widely, from their supposed starting point in the solar year. For more information about each of the calendars, see the detailed chronological tables that have been compiled by Chris Bennett.
Babylonian (Jewish) calendarNisanu (Nisan) = April
To convert Babylonian dates into Julian dates, see the Babylonian Calendar Converter.
To convert Egyptian dates into Julian dates, see the Date Converter for Ancient Egypt.
Greek (Athenian) calendarHecatombaeon = July/August
Macedonian calendarDius = October
Roman (pre-Julian) calendarJanuarius (29 days)
To convert Roman dates into Julian dates, see the Roman Calendar Conversion Table, with Guidance.
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