Bengal or endonym Bangla is a historical geographical, ethnolinguistic and cultural term referring to a region in the eastern part of the Indian subcontinent at the apex of the Bay of Bengal. The region of Bengal proper is divided between modern-day sovereign nation of Bangladesh and the Indian state of West Bengal.

The Bengali Calendar or Bangla Calendar, colloquially, is a solar calendar used in the Bengal region of the South Asia. 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. Unlike the traditional Indian Hindu calendar which starts with the month of Chaitra, the Bengali calendar starts with Boishakh because of the reforms made during the reign of the Mughal Emperor Akbar in Mughal Bengal. The first day of the Bengali year is known as Pohela Boishakh which is a public holiday in Bangladesh.