Bengal is one of the most densely populated regions on Earth, with an estimated population of more than 250 million people and a population density exceeding 900 people per square kilometer. Most of the Bengal region lies in the low-lying Ganges Delta, the world's largest river delta. In the southern part of the delta lies the Sundarbans, the world's largest mangrove forest and home of the Bengal tiger. In the coastal southeast lies Cox's Bazaar, the world's longest beach with a length of 120 km (75 mi). While most of region is rural and agrarian, it includes two megacities: Kolkata (previously Calcutta) and Dhaka (previously Dacca).
The Bengal region has a rich literary and cultural heritage and immensely influenced South Asian history through the Bengal Renaissance during the 19th and early 20th centuries and the Bengali Language Movement in the mid-20th century. The Bengal was the seat of western science education and a major industrial hub in pre and post independent India and reshaped the modern Indian culture and the Bengali people made important contributions to the revolutionary movement for Indian independence and the overall Indian independence movement, and successfully prosecuted the Bangladesh Liberation War.