Nippur calendar

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July 1, 2026

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The Nippur calendar was a chronological system used in ancient Mesopotamia, which is now modern-day Iraq. This calendar was a lunisolar system, meaning its months were based on the cycles of the Moon, while its years were aligned with the solar year to match the seasons.123

The Nippur calendar became widely accepted around the 2nd millennium BCE. It was standardized by the Babylonian empire in the 18th century BCE, beginning on Nisanu 1 in the spring. The calendar reconciled the approximately 354-day lunar year with the solar year of about 365 days by occasionally adding an extra month, a practice known as intercalation. By around 380 BCE, a regular 19-year cycle was used, with 7 of those years having an extra month, ensuring the start of the year remained near the spring equinox.431

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Mesopotamian religion
Sacred times
…2nd millennium bce did the Nippur calendar attain general acceptance. The nature of the festivals in these various sacred calendars sometimes reflected the cycle of agricultural activities, such as celebrating the ritual hitching up of the plows and, later in the year, their unhitching, or rites of sowing, harvesting, and…
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…2nd millennium bce did the Nippur calendar attain general acceptance. The nature of the festivals in these various sacred calendars sometimes reflected the cycle of agricultural activities, such as celebrating the ritual hitching up of the plows and, later in the year, their unhitching, or rites of sowing, harvesting, and…
Read More