Since prehistoric times, 12 months of Bengali Bengal celebrated in the Indian subcontinent according to the habitual Hindu solar eclipse. This solar outdo begins in the Gregorian calendar in the internal of April. Hindu solar day was celebrated as an primary job of Assam, Bengal, Kerala, Manipur, Nepal, Orissa, Punjab, Tamil Nadu and Tripura on the elementary day.
After the Mughal reach a decision began, the public management in progress in the sub-continent according to the Hijri calendar. Which is based on Chandramas. The moon day is minus than 11 to 12 existence minus than the solar year. as the solar day is 365 days, and the planetary day is 354 days. For this reason, the downpour spice is not well. 
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Initially, the label was 'Tarikh-e-Elahi'. The names of this month of Moglai were unpretentiously in Persian, such as: Kaarar Day, Urdu Bahish, Khordad, Arrow, Muradad, Shahriar, Mehr, Azan, Aazar, De, Bahman and Iskandar Miz. Later, 'Dat-e-Elahi' is acknowledged as 'crop year', 'bangabda' or 'bangla year'.
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