Civilisational history of Bangladesh dates back over four millennia, to the Chalcolithic. The country’s early documented history featured successions of Hindu and Buddhist kingdoms and empires, vying for regional dominance.

Islam arrived during the 6th-7th century AD and became dominant gradually since the early 13th century with the conquests led by Bakhtiyar Khalji as well as activities of Sunni missionaries such as Shah Jalal in the region. Later, Muslim rulers initiated the preaching of Islam by building mosques. From the 14th century onward, it was ruled by the Bengal Sultanate, founded by king Shamsuddin Ilyas Shah, beginning a period of the country’s economic prosperity and military dominance over the regional empires, which was referred by the Europeans to as the richest country to trade with.[1] Afterwards, the region came under the Mughal Empire, as its wealthiest province. Bengal Subah generated almost half of the empire’s GDP and 12% of the world’s GDP,[2][3][4] larger than the entirety of western Europe, ushering in the period of proto-industrialization.[5] The population of the capital city, Dhaka, exceeded a million people.

Following the decline of the Mughal Empire in the early 1700s, Bengal became a semi-independent state under the Nawabs of Bengal, ultimately led by Siraj ud-Daulah. It was later conquered by the British East India Company at the Battle of Plassey in 1757. Bengal directly contributed to the Industrial Revolution in Britain but led to its deindustrialization.[6][7][8][9] The Bengal Presidency was later established.

The borders of modern Bangladesh were established with the separation of Bengal and India in August 1947, when the region became East Pakistan as a part of the newly formed State of Pakistan following the end of British rule in the region.[10] Proclamation of Bangladeshi Independence in March 1971 led to the nine-month long Bangladesh Liberation War, that culminated with East Pakistan emerging as the People’s Republic of Bangladesh.

After independence, the new state endured famine, natural disasters, and widespread poverty, as well as political turmoil and military coups. The restoration of democracy in 1991 has been followed by relative calm and rapid economic progress.

The Oxford History of India categorically claims that there is no definitive information about Bengal before the third century BCE. It is believed that there were movements of Indo-Aryans, Dravidians and Mongoloids, including a people called Vanga, into Bengal.[16]

The Bengal delta was made up of thick jungles and wetlands for several millennia. A major part of this geography lasted till historical times. The loss of the jungle was due to human activity. Bengal had an early human presence. But there is no consensus for the time frame of the first human activity in Bengal nor are there plenty of remains. One view contends that humans entered Bengal from China 60,000 years ago. Another view claims that a distinct regional culture emerged 100,000 years ago. There is weak evidence for a prehistoric human presence in the region.[17] There is scant evidence of a human presence during the Neolithic and Chalcolithic eras.[16] This could be because of the shifts in the rivers’ courses.[16] The Bengali climate and geography is not suitable for tangible archaeological remains. Due to lack of stones the early humans in Bengal probably used materials such as wood and bamboo that could not survive in the environment. South Asian archaeologists have tended to focus on other parts of the subcontinent. Archaeologists interested in Bengal have focused on more recent history.[17]

Archaeological discoveries are almost entirely from the hills around the Bengal delta. West Bengal and Bangladesh’s eastern terrain offer the best source of information about the early peoples of Bengal. Industries of fossil-wood manufacturing blades, scrapers and axes have been discovered in Lalmai, Sitakund and Chaklapunji. These have been connected with similar findings in Burma and West Bengal. Large stones, thought to be prehistoric, were constructed in north eastern Bangladesh and are similar to those in India’s nearby hills. Farming was practised before the first millennium BCE. West Bengal holds the earliest evidence of settled agrarian societies.[18]

Agricultural success gave ground in the fifth century BCE for a stationary culture and the emergence of towns, cross-sea trade and the earliest polities. Archaeologists have uncovered a port at Wari-Bateshwar which traded with Ancient Rome and Southeast Asia. The archaeologists have discovered coinage, pottery, iron artefacts, bricked road and a fort in Wari-Bateshwar. The findings suggest that the area was an important administrative hub, which had industries such as iron smelting and valuable stone beads. The site shows widespread use of clay. The clay, and bricks, were used to build walls.[19] The most famous terracotta plaques, made by clay, are from Chandraketurgah and depicts deities and scenes of nature and ordinary life.[20] The early coinage discovered in War-Bateshwar and Chandraketugarh (West Bengal, India) depict boats.[21]

Many of archaeological excavations in Bangladesh revealed evidences of the Northern Black Polished Ware (NBPW or NBP) culture of the Indian Subcontinent (c. 700–200 BC), which was an Iron Age culture developed beginning around 700 BC and peaked from c. 500–300 BC, coinciding with the emergence of 16 great states or mahajanapadas in Northern India, and the subsequent rise of the Mauryan Empire. The eastern part of ancient India, covering much of current days Bangladesh was part of one of such mahajanapadas, the ancient kingdom of Anga, which flourished in the 6th century BC.[22][verification needed]

Well developed towns had emerged by 300 BCE such as Tamralipti ( present-day Tamluk, West Bengal, India), Mahasthan and Mainamati.[23] Instead of the seaside, main towns sprang up by the riversides.[24] Mahasthan contains the earliest piece of writing in Bangladesh, a stone inscription. It indicates that the site was an important town in the Maurya empire. Mahasthan is believed to have then been a provincial centre.[23] The inscription, in Prakrit, apparently contains a command to stock up supplies in case of an emergency.[25] The inscription is called the Mahasthan Brahmi Inscription.[20] Bengal was the eastern frontier of the Mauryan empire. Western Bengal with its port of Tamralipti achieved importance under the Mauryas.[24]

A prominent view in scholarship is that the Mauryan and Gupta empires exercised authority over most parts of the Bengal delta. The incomplete evidence which exists suggests that Bengal’s western rather than eastern regions were parts of larger empires.[26] The ancient zones in Bengal were the Bhagirathi-Hooghly basin, Harikela, Samatata, Vanga and Varendra.[27] Vanga is believed to be central Bengal, Harikela and Samitata were apparently Bengal’s eastern zones and Varendra was northern Bengal.[21] The names of sites indicate that Tibeto-Burman, Austro-Asiatic and Dravidian languages were spoken by the majority of people. Indo-European languages became prominent from 400 BCE.