Mukherjee founded the Bharatiya Jana Sangh on 21 October 1951 in Delhi, becoming its first president. In the 1952 elections, the Bharatiya Jana Sangh (BJS) won three seats in the Parliament of India, including Mukherjee's. He had formed the National Democratic Party within the Parliament. It consisted of 32 members of the Lok Sabha and 10 members of the Rajya Sabha; however, it was not recognised by the speaker as an opposition party. The BJS was created with the objective of nation-building and nationalising all non-Hindus by "inculcating Bharatiya Culture" in them. The party was ideologically close to the RSS and widely considered the proponent of Hindu nationalism.