The flag was designed by Sachindra Prosad Basu, Secretary, Anti-circular Society of Calcutta and Sukumar Mitra, a close associate of Surendranath Banerjee. Dr. Bhupendranath Dutta (younger brother of Swamy Vivekananda) and editor of the then Bengali weekly Jugantar, wrote in his book ‘Bharater Dwitiya Swadhinater Sangaram –Aprakashita Rajnaitik Itihas (India’s Second War of Independence - The Untold History) published in 1926, that Sukumar Mitra And Sachindra Prisad Basu while designing the flag were influenced by the French Tricolore and the message “Liberte, Egalite & Fraternite .
The Flag was later hoisted by the Congress President Dadabhoy Naoroji, the Grand Old Man of India (1825-1917) at the Calcutta Session of Congress in December 1906.
A strikingly similar to the Calcutta flag, with minor deviations was proudly waved by Madame Cama on August 22, 1907 at the International Socialist Congress at Stuttgart, Germany. Waving the flag she declared “ This the flag of Indian Independence. Behold, it is born. It is already sanctioned by the blood of martyred Indian youths …”
Madame Cama in one of her speech stated "This is the flag for which Khudiram Bose and Prafulla Chaki died".
The proposed stamp on Prafulla Chaki is scheduled to be released in December 2010.
The above explains how the Calcutta flag reached Madame Cama through Hem Chandra Kanungo.