Under the Mughals, agricultural taxes were collected according to the Hijri calendar.
However, as the Hijri calendar is a lunar calendar, the agricultural year does not coincide with the fiscal.
As a result, farmers were hard-pressed to pay taxes out of season. In order to streamline tax collection, the Mughal Emperor akbar ordered a reform of the calendar.
Accordingly, Fatehullah Shirazi, a renowned scholar and astronomer, formulated the Bangla year on the basis of the lunar Hijri and Bangla solar calendars.
The new Fasli San (agricultural year) was introduced on 10/11 March 1584, but was dated from Akbar's ascension to the throne in 1556.
The new year subsequently became known as bangabda or Bengali year.
Celebrations of Pahela Baishakh started from Akbar's reign.
It was customary to clear up all dues on the last day of Chaitra. On the next day, or the first day of the new year, landlords would entertain their tenants with sweets. On this occasion there used to be fairs and other festivities.
In due course the occasion became part of domestic and social life, and turned into a day of merriment. The main event of the day was to open a halkhata or new book of accounts. This was wholly a financial affair.
In villages, towns and cities, traders and businessmen closed their old account books and opened new ones. They used to invite their customers to share sweets and renew their business relationship with them.
This tradition is still practised, especially by jewellers. New year's festivities are closely linked with rural life in Bengal.
Usually on the day everything is scrubbed and cleaned. People bathe early in the morning and dress in fine clothes and then go to visit relatives, friends and neighbours.
Special foods are prepared to entertain guests. Baishakhi fairs are arranged in many parts of the country.
Various agricultural products, traditional handicrafts, toys, cosmetics as well as various kinds of food and sweets. are sold at these fairs.
The fairs also provide entertainment, with singers and dancers staging jatra, pala gan, kavigan, jarigan, gambhira gan, gazir gan and alkap gan. They present folk songs as well as baul, marfati, murshidi and bhatiali songs.
Narrative plays like laily-majnu, yusuf-zulekha and Radha-Krishna are staged. Among other attractions of these fairs are puppet shows and merry-go-rounds.
Many old festivals connected with new year's day have disappeared, while new festivals have been added. With the abolition of the zamindari system, the punya connected with the closing of land revenue accounts has disappeared.
Kite flying in dhaka and bull racing in munshiganj used to be very colourful events.
Other popular village games and sports were horse races, bullfights, cockfights, flying pigeons, boat racing.
Some festivals, however, continue to be observed, for example, bali or wrestling in Chittagong and gambhira in Rajshahi.
Observance of Pahela Baishakh has become popular in the cities. Early in the morning people gather under a big tree or on the bank of a lake to witness the sunrise. Artistes present songs to welcome the new year.
People from all walks of life wear traditional Bengali dresses: young women wear white sarees with red borders and adorn themselves with bangles, flowers, and tips.
Men wear white pyjamas or dhoti and kurta. Many townspeople, start the day with the traditional breakfast of panta bhat (cooked rice soaked with water), green chillies, onion, and fried hilsa fish.
The most colourful new year's day festival takes place in Dhaka.
Large numbers of people gather early in the morning under the banyan tree at Ramna Park where chhayanat artistes open the day with Tagore's famous song, Eso he Baishakh eso eso (Come O Baishakh, come), welcoming Baishakh.
A similar ceremony welcoming the new year is also held at the Institute of Fine Arts, university of dhaka.
Students and teachers of the institute take out a colourful procession and parade round the campus. Social and cultural organisations celebrate the day with cultural programmes. Newspapers bring out special supplements.
There are also special programmes on radio and television. The historical importance of Pahela Baishakh in the Bangladesh context may be dated from the observance of the day by Chhayanat in 1965.
In an attempt to suppress Bengali culture, the Pakistan Government had banned tagore songs.
Protesting this move, Chhayanat opened their Pahela Baishakh celebrations at Ramna Park with Tagore's song welcoming the month.
The day continued to be celebrated in East Pakistan as a symbol of Bengali culture.
After 1972 it became a national festival, a symbol of the Bangladesh nationalist movement and an integral part of the people's cultural heritage.