Kolkata: As a teenager, Uttam Shaha says he used to watch scornfully from his bedroom window as men in brown shorts performed martial exercises in a car park below. Like many Indians then, he viewed the Rashtriya Swayamsevak Sangh (RSS) as a fringe group.

Now 43, Shaha is a recent RSS recruit in Kolkata, the capital of West Bengal. He joined about 50 volunteers for an indoctrination meeting last year at that same car park near RSS headquarters in Kolkata. As dusk set in, they sat cross-legged on a faded rug before a statue of Bharat Mata, a representation of India in the form of a mother goddess.

Ramapada Pal, the RSS’s chief preacher in the state, espoused a message of Hindu supremacy. Everyone must acknowledge “the superiority of the Hindu kingdom,” he said. “If a Muslim living in India chooses their god before India, then why should he be allowed to live in our country? This country belongs to Hindus first.” The RSS says its membership is growing. RSS Joint General Secretary Dattatreya Hosabale predicted the number of RSS branches in West Bengal would rise to 1,200 next year from 650 in 2013. There is no independent measure of RSS membership.

The group’s message has particular resonance in West Bengal, which borders Bangladesh. An influx of Bangladeshi immigrants has boosted the number of Muslims, who now make up 27% of the population in West Bengal, an interior ministry official said. Hindus remain a majority, but their share of the population declined by 2.2% points between the 2001 and 2011 census.

Muslims from Bangladesh are feasting on our resources, says RSS

Rahul Sinha, the BJP’s head in the state, said the RSS was the “guiding force in a war to win the ancient Hindu soul of India. Muslims are coming from Bangladesh and feasting on our resources,” he said. “New mosques and madrassas have been set up in every corner.” Shaha, the new RSS recruit, said he turned to the RSS last July after his niece married a Muslim and converted to Islam, shaming his well-to-do family. “I had to protect my Hindu roots – they had been threatened,” he said.

The RSS talked to him about reconverting his niece, but Shaha said the move was blocked when she threatened to lodge a police complaint against her family if they tried to interfere in her personal life. Shaha said he campaigned for the BJP in the municipal elections this year and was ready to do the same for the party in next year’s state election. “My mission is to make India a Hindu nation,” he said.