In the early 19th century, Kolkata has been divided into two separate areas, one British (known as the White Town), the other Indian (known as Black Town). Even at the time, the poverty of the "black city" Slums was considered shocking. The city has undergone rapid industrial growth of the 1850's, especially in the sectors of textiles and jute, which caused a massive investment in infrastructure projects, such as railways and telegraph by the British Government. The coalescence of Indian culture and British led to the emergence of a new class of urban Indians Babu - whose members are often bureaucrats, professionals, read newspapers, were Anglophiles, and generally higher belonged to the caste Hindu communities. Throughout the nineteenth century, a socio-cultural reform, often referred to as the Bengal Renaissance led to the rise of the people. In 1883, Surendranath Banerjea organized a national conference - the first of its kind in India in the nineteenth century. Kolkata gradually become a centre of the movement for India's independence, particularly the revolutionary organizations. The 1905 partition of Bengal on communal land led to the widespread unrest of opinion and the boycott of British products (Swadeshi movement). These activities, along with the disadvantage administratively Kolkata in the eastern suburb of India, have prompted the British to move the capital of New Delhi in 1911.

Kolkata Port in 1945. It was an important port for military WW II. The port city was bombed twice by the Japanese during the Second World War. As food stocks have been diverted to feed the Allied troops, millions starved to death during the famine of Bengal in 1943.In 1946-2000 people Partition of India has also created intense violence and a change in the data Demographics - a large number of Muslims left for East Pakistan, while hundreds of thousands of Hindus have fled to the city.

During the years 1960 and 1970, serious energy shortages, strikes and violent Marxist-Maoist movement - the Naxalites - damaged a large part of the city infrastructure, leading to economic stagnation. In 1971, war between India and Pakistan led to the massive influx of thousands of refugees into Kolkata causing enormous pressure on its infrastructure. In mid-1980, Mumbai, Kolkata that India has exceeded the most populous of the city. Kolkata has been a solid base of communism as India's West Bengal has been ruled by the CPI (M) Left Front dominated for three decades now - in the world's oldest democratically elected communist government. The economic recovery in the city has intensified since the economic reforms introduced in India by the Central Government in mid-1990. Since 2000, the information technology (IT) services of the city revitalized stagnant economy. The city is also experiencing growth in the manufacturing sector.