At the close of the First War of Indian Independence in 1857, the British government established an imperial headquarters on the subcontinent at Kolkata. Over the next twenty-plus years, administrators set out to engage the natives in order to avoid the rebellions which forced the East India Company to relinquish control in the first place. By 1883, the responsibility for developing this coalition became the personal mission of a retired district officer named Allan Octavian Hume. Capitalizing on the simmering desire amongst Indians for independence, he composed an open letter for a carefully-chosen group of graduates from the University of Calcutta explaining they would have to “make a resolute struggle to secure greater freedom for yourselves and your country.”

The idea of the Congress took concrete shape during a meeting of the Theosophical Convention in Madras in December 1884. In March 1885 a notice was issued convening a meeting at Pune in December of the same year, but due to a severe plague outbreak there, the meeting was later shifted to Bombay. Granted permission by the governor, the Viceroy understood Hume’s intention — coupled with that of natives like Womesh Chandra Bonnerjee and others — to be the creation of a single point of contact for the varying concerns locals might bring to the colonial government.

On December 28, 1885, a group of 72 delegates gathered at Gokuldas Tejpal Sanskrit College in Mumbai to form the Indian National Congress (INC) with W.C. Bannerjee in the chair and Hume assuming office as the General Secretary. Other important delegates included Dadabhai Naoroji, Justice Ranade, Pherozeshah Mehta, K.T. Telang and Dinshaw Wacha. Defining the objective of the Congress, the president spoke of the “promotion of personal intimacy and friendship among all the more earnest workers in our country’s cause in the parts of the empire and eradication of race, creed or provincial prejudice and fuller development of national unity”.

Subsequently, the Congress led India to Independence in 1947 after a long but remarkably peaceful struggle.

Reference:

http://www.mapsofworld.com/on-this-day/december-28-1885-the-indian-national-congress-is-founded-in-mumbai-

http://www.indianetzone.com/41/history_indian_national_congress.htm