Why was the Mayan calendar such an important thing?

The Mayan Calendar determines dates by its position in both the Tzolkin and the Haab calendars.” Together, this creates “18,980 unique date combinations, they use this to identify each day within a cycle lasting about 52 years. A Calendar Round is the completion of each cycle period.

Explanation:

The 260-day calendar was used to adjudge, really  important activities related to the gods and humans. It was used to name people , predict the future, decide on auspicious dates for battles, marriages, and so on.

the second significant cause of the great migration was the desire of black southerners to escape segregation, known euphemistically as jim crow. rural african american southerners believed that segregation - and racism and prejudice against blacks - was significantly less intense in the north.

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