Chittagong (Bengali: চট্টগ্রাম, Chôţţogram) is a commerce and industry hub, and a port city, in southeastern Bangladesh and the capital of an eponymous district and division. Built on the banks of the Karnaphuli River, the city is home to Bangladesh's busiest seaport and has a population of over 5.5 million, making it the second largest city in the country.

A trading post since the 9th century, Chittagong has a multicultural heritage of Islamic, Hindu and Buddhist traditions, as the result of different waves of settlements throughout the Middle Ages and well into the start of the British Raj. A few parts of Chittagong were developed in the early 20th century under the British to accommodate a railway hub. The city also became a focal point for revolutionary activities against the British, notably the armed uprising led by Surya Sen in 1930. It was also an important military base and supply point for Allied forces during the Burma Campaign in World War II. After the partition of India in 1947, Chittagong became part of East Pakistan. It was then that several key outlying areas were included into the city of Chittagong, including Agrabad, a modern commercial centre today. Chittagong regained prominence as an important investment destination and sea port in the eastern part of a newly independent country. In 1971, as East Pakistanis rebelled against West Pakistan’s refusal to accept results of the 1970 Pakistan General Election, the declaration of East Pakistan's secession into Bangladesh was announced in Chittagong. The city went onto witness atrocities and naval blockades during the liberation war that followed. Chittagong's development has been heavily affected by neglectfulness by the government, and centralization of the capital has taken toll to the cities development and growth.