Bangla calendar

The Bengali Calendar or Bangla Calendar (বঙ্গাব্দ Bônggabdô or Banggabda) is a solar calendar used in the region of Bengal. A revised version of the calendar is the national and official calendar in Bangladesh and an earlier version of the calendar is followed in the Indian states of West Bengal, Tripura and Assam. The New Year in the Bengali calendar is known as Pôyla Bôishakh.

The Bengali era is called Bengali Sambat (BS) or the Bengali year (বাংলা সন Bangla Sôn, বাংলা সাল Bangla sal, or Bangabda) has a zero year that starts in 593/594 CE. It is 594 less than the AD or CE year in the Gregorian calendar if it is before Pôhela Bôishakh, or 593 less if after Pôhela Bôishakh.

A revised version of the Bengali calendar was officially adopted in Bangladesh in 1987. Among the Bengali community in India, the tradition Bengali Hindu calendar continues to be in use, and it sets the Hindu festivals.

According to Shamsuzzaman Khan, and Nitish Sengupta, the origin of the Bengali calendar is unclear.

Some historians attribute the Bengali calendar to the 7th century Hindu king Shashanka. The term Bangabda (Bangla year) is found too in two Shiva temples many centuries older than Akbar era, suggesting that Bengali calendar existed long before Akbar's time.

Hindus developed a calendar system in ancient times.Jyotisha, one of the six ancient Vedangas, was the Vedic era field of tracking and predicting the movements of astronomical bodies in order to keep time. The ancient Indian culture developed a sophisticated time keeping methodology and calendars for Vedic rituals.

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