It was established on 21 October 1951 in Delhi by three founding members: Shyama Prasad Mukherjee, Balraj Madhok and Deendayal Upadhyaya.

Many members of the right-wing Hindu nationalist Rashtriya Swayamsevak Sangh (RSS) began to contemplate the formation of a political party to continue their work, begun in the days of the British Raj, and take their ideology further.

[13][14][15] Mainly two reasons led to the formation of Jan Sangh- first was the Liaquat–Nehru Pact and second, the ban on RSS after the assassination of Mahatma Gandhi.

(Patiala and East Punjab States Union), Delhi, West Bengal, Rajasthan, Uttar Pradesh, Madhya Bharat were already established before it was formally founded at national level.

[25] The BJS leadership fervently supported a strong policy against Pakistan and China, and were averse to communism and the Soviet Union.