Since Mr. Modi came to power, Mr. Ramdev's company has received more than an estimated $46 million in discounts for land acquisitions in states controlled by the BJP.

Narendra Modi leaned to whisper in the ear of the man sitting cross-legged and barefoot next to him, the one clad in saffron robes with a long beard and squinty gaze. It was late in the afternoon of March 23, 2014 in New Delhi and the start of national elections was a fortnight away.

A few minutes later, the yoga guru and entrepreneur known as Baba Ramdev turned to a microphone and urged the crowd before him to mobilize votes for Mr. Modi: “You'll make other people understand, won't you? You won't sit at home, will you?” The crowd roared back, “No!"

Mr. Modi grinned. Mr. Ramdev laughed. The politician and the co-founder of a billion-dollar consumer products business were both headed to the pinnacle of a right-wing Hindu movement that seeks to shape the destiny of the world's fastest-growing major economy. About two months after the rally, when voting had rolled across the vast country, Mr. Modi's Bharatiya Janata Party (BJP) swept the long-ruling Congress Party from power.

Mr. Modi had prevailed, in part, with promises to reform the economy and root out corruption. His business-friendly language won widespread praise. But it was also his trumpeting of a Hindu nationalist message the idea that India should be ruled as a nation by and for Hindus that helped propel him to victory.

Modi, Ramdev and the BJP

In ways not previously disclosed, Mr. Modi and Mr. Ramdev, each a product of the Hindu right, owe part of their success to the other. The yoga guru is one of the most instantly recognisable figures in India and his company's traditional foods and health supplements are among the country's fastest-growing brands. He tapped his following as a TV yoga celebrity and deployed resources from his consumer goods empire, mobilising voters and synchronising messaging with the BJP in a 2014 campaign that was larger and more tightly coordinated with Mr. Modi's party than is publicly known.

PM Narendra Modi with Baba Ramdev in 2014. | Photo Credit: R.V. Moorthy

In return, leading BJP figures have endorsed Mr. Ramdev's vision for India, a populism laced with assertions of Hindu primacy that twins nostalgia for ancient glory with suspicion of foreign influence.

Since Mr. Modi came to power, Mr. Ramdev's company has received more than an estimated $46 million in discounts for land acquisitions in states controlled by the BJP, according to a Reuters review of state government documents, interviews with officials and real estate estimates. It gained access to other land free of charge. The firm, Patanjali, has also received something of an official imprimatur from a newly created ministry and BJP leaders.

It is a partnership that reveals the inner workings of influence and money in Mr. Modi's India, where the relatively secular world view of the Congress party he ousted is being chipped away.

Three weeks after the rally in New Delhi, a trust controlled by Mr. Ramdev released a YouTube video in which senior BJP members posed with a signed “Shapath Patra”, Hindi for “Oath.”

The document, reviewed by Reuters, laid out nine pledges. These included the protection of cows, an animal held sacred in Hinduism, and reforming much of Indian life to make it "swadeshi,” a word used by Hindu nationalists to invoke that which is truly Indian. That set of beliefs, the oath said, extended to the courts, government, cultural institutions and education. The five signatories pictured in the video included the present ministers of foreign affairs, finance, internal security and transportation. None of the ministers responded to questions about the pledge.

“These renowned BJP leaders have signed their names on these oaths because of the hope that I have generated among millions, I want people to see a change in government,” Mr. Ramdev said in the video. “We have created these nine points.”

A spokesman for one of the signatories, BJP party elder and former deputy prime minister L.K. Advani, at first denied knowledge of the document and then said it was unrelated to Ramdev. “It was the party's program and all the senior leaders had signed this document,” Mr. Advani's personal secretary Deepak Chopra said.

A Patanjali official familiar with the document said senior members of the BJP had put their names to it as a condition of Mr. Ramdev's support.

Booming business

Mr. Ramdev's business has boomed since the BJP took power. Revenues at his consumer goods enterprise are soaring from about $156 million in the financial year ending March 2013 to more than $322 million in the year to March 2015, according to financial filings. In early May, Ramdev said revenues in the financial year just ended had jumped to about $1.6 billion.

“Within half a year of Modi coming to power, his administration transformed an obscure government department of traditional Indian medicine into a standing ministry dedicated to popularising, among other things, the practice of yoga and the use of ayurvedic products, for which Patanjali is a market leader.” | Photo Credit: PTI

The firm's products range from toothpaste to clarified ghee butter and household cleaning materials. They are found in every corner of the country, from the scantest villages to teeming cities. Its foods, which include rice, biscuits and chutney, are sold in the canteens of India's security forces and served on some tables in the nation's parliament.

Advertisements for Patanjali's products stress that they are ayurvedic, meaning they are rooted in ancient Indian tradition. The ads echo the talking points of Modi's support base by appealing to consumers' patriotism, urging them to avoid giving cash to foreign firms.

“As East India Company plundered our country for 200 years," reads one advertisement, referring to the British company that colonised India during the 18th and 19th centuries, “likewise these multinationals are exploiting our country by selling their harmful and dangerous chemical products. Beware!"

Close friend Modi

Mr. Ramdev is at once effusive about Mr. Modi and reluctant to give details about his relationship with the prime minister. “Modi-ji is a close friend,” he said, using an honorific suffix, at an interview last year at his home in the northern town of Haridwar at the base of the Himalayas, where poplar trees peeked over high compound walls and black-clad security held assault rifles.

Mr. Modi’s office did not respond to questions for this story.

Mr. Ramdev burst into politics in 2011 when he joined anti-corruption protests directed against the ruling Congress Party. | Photo Credit: Ramesh Sharma

Of his role in Mr. Modi’s success in 2014, Mr. Ramdev said, “It’s not good form to praise yourself.” He added, “I won’t say much, but I prepared the ground for the big political changes that occurred.”

Since Mr. Modi took office in May 2014, Patanjali has acquired almost 2,000 acres of land for building factories, research facilities and establishing supply chains of herbs for its products, according to state land documents and interviews with officials. During the rule of the previous Congress-led government the firm had been selling large tracts of its land holdings. Two of the four acquisitions exceeding 100 acres were in states controlled by the BJP. A third was in an area where the governing party was in the process of partnering with the BJP.

In the BJP-controlled states, Patanjali received a discount on the land purchased of 77% off market prices, according to state government documents, interviews with officials and land values provided by local real estate agents. The company has pledged to use the property to create more jobs with new factories, answering a major need in India, where millions of people are reaching working age each year.

Official reporting of land transactions in India is patchy, especially of deals involving smaller acreages. But some do surface. For example, Patanjali received a discount of more than $10 million, or 88%, on a 40-acre plot in the BJP state of Madhya Pradesh last year, according to interviews with a state official and real estate brokers.

Neither the prime minister's office nor Patanjali executives, including Mr. Ramdev, responded to written questions about the transactions, which were lawful.

At a stone-laying ceremony for a Patanjali food processing plant in the central Indian city of Nagpur last September, one of the signers of the oath in the Ramdev video, Transportation Minister Nitin Gadkari, made a personal appearance. A video recording of the event showed Patanjali's Managing Director Acharya Balkrishna turning to Gadkari. “We want a road” leading to the site of the planned factory, Mr. Balkrishna said.

From his place on a white sofa, the minister smiled. “This road you're talking about, I've decided to make it a national highway. Once you start your work, we'll issue a tender,” he said.

Mr. Ramdev, who sat between Mr. Gadkari and the state's BJP chief minister, Devendra Fadnavis, laughed and applauded.

Mr. Gadkari did not respond to questions.

Patanjali had paid some 590 million rupees (about $9.1 million at current rates) for the 234-acre property. The land abuts a special economic zone (SEZ) promoted by the state and its market price was more than 2.6 billion rupees (about $40.5 million), according to comments submitted to the state legislature by Mr. Fadnavis.

“The land outside the SEZ was given cheaply to Patanjali because it has not been developed. There is no approach road," Mr. Fadnavis said in a written reply to an opposition lawmaker who questioned the price.

A trip to the site found it sits just on the other side of a small wall from a police and fire station and across the street from a corporate park. A road under construction at the back of the property will be accessible to Patanjali. A spokesman for the government development authority that oversees the area said the deal included commitments to the community: buying raw materials from local sources, training 2,000 farmers in new skills and employing 5,000 people from nearby villages. "Patanjali is an Indian company, an ayurvedic company, so many states give them free land,” the spokesman, Deepak Joshi, said.

Undeveloped land from Assam

The largest transaction was a transfer of some 1,200 acres of undeveloped land in the eastern state of Assam in October and December 2014. The deal was struck by the Bodoland Territorial Council, an agency that oversees an autonomous region and is controlled by the Bodoland Peoples Front (BPF). The BPF had broken from a Congress-led coalition in the state earlier in 2014, before allying with the BJP in January 2016. Kampa Borgoyary, deputy chairman of the council and spokesman for the BPF, said the party “had known from the beginning it would support the BJP.”

According to state legislature documents reviewed by Reuters, the land was “allotted without cost” — given free of charge — to Patanjali Yogpeeth, a trust controlled by Patanjali Managing Director Balkrishna and Ramdev, on the condition that it be used for the “preservation and promotion of cow breeds.” The arrangement permitted Patanjali to collect medicinal plants, a vital component for its expanding line of natural products. Borgoyary said the deal reflected the council's confidence that Patanjali would “protect” the land.

Commercial transactions involving land of this sort are unusual, making it difficult to put a value on the plot.

In Uttar Pradesh, where Mr. Ramdev's company acquired a tract of land not overseen by the BJP or an administration favorable to the ruling party, the savings were smaller: 300 acres of land at 25% below market prices in November 2016. The discount was in keeping with standard practice for deals that size, the chief executive officer of the industrial area said.

Patanjali and, to a lesser degree, other Indian companies attached to what are known colloquially as “god men” and other spiritual leaders have received government support and tax breaks under Modi. The company's rising fortunes appear to be putting pressure on its foreign rivals.

Unilever's head of investor relations, Andrew Stephen, spoke about intense local competition in India's personal care market, including from Patanjali, when presenting the firm's third quarter earnings last year. Hindustan Unilever's Chief Financial Officer P.B. Balaji said this month the firm was introducing natural variants of its existing brands.

In another sector, a Reuters investigation earlier this year found that the ideological parent of the BJP was instrumental in a lobbying campaign that supported an Indian firm and its allies against Monsanto Co, the world's largest seed company. In response to a Reuters' query about that turn of events, a Monsanto executive released a statement saying it was "unfortunate that these disputing companies sought policy interventions to address a bilateral matter.”

Product support

Within half a year of Mr. Modi coming to power, his administration transformed an obscure government department of traditional Indian medicine into a standing ministry dedicated to popularising, among other things, the practice of yoga and the use of ayurvedic products, for which Patanjali is a market leader.

The ministry now regulates many of Patanjali's products. It has participated in promotional and training sessions with Ramdev and his organization, from online presentations to a mass yoga demonstration with the minister of housing and urban development on New Delhi's central boulevard.

The Ministry of Finance in 2015 defined yoga as a "charitable purpose,” reducing the associated tax burden. That particularly benefits corporations such as Patanjali that have espoused support for the kind of Hindu nation envisaged by the ruling party. The finance ministry is headed by Arun Jaitley, who was one of the signatories of the pledge before the 2014 elections. Mr. Jaitley, Mr. Ramdev and other Patanjali executives did not respond to questions about the policy.

Modi's BJP is pushing back against the secular legacy of its political predecessors in what some party leaders have referred to as a “cultural revolution” in a nation that is almost 80 percent Hindu, with Muslims forming roughly 14 percent.

As the BJP wins a steady march of state elections, the party and its ideological backers are increasingly public about their nationalist, Hindu agenda. On the ground, that movement is accompanied by multiple incidents of Hindu mobs beating or killing Muslim men and other minorities because of suspicions they were involved with the slaughter of cows.

Modi has spoken out against the so-called cow vigilantes.

No ordinary business

Mr. Modi and Mr. Ramdev have much in common. Like Mr. Modi, the son of a train-station tea seller, Mr. Ramdev came from humble beginnings. The son of a farmer, he was born in north India in the mid-1960s.

Jeevraj Patel, a businessman in the construction sector, said that when he first met Ramdev in 1992, the “swami” was running small yoga camps and mixing medicinal herbs. He lived in an ashram, a spiritual retreat, in Haridwar.

“The more slots the channel put Ramdev on, the more requests it received from viewers to see him.” | Photo Credit: Ramesh Sharma

Patanjali Managing Director Balkrishna said he and Mr. Ramdev started their first enterprise in 1995 as they learned how to make ayurvedic medicines and supplements. They had ₹3,500 (about $90 at the time) and borrowed ₹10,000 more.

Mr. Balkrishna described the two of them making fires to mix ingredients for chyawanprash, a traditional jam, and then carrying vats of it home on their heads as neither had the money for a rickshaw ride.

Mr. Ramdev might have remained a local character if not for a spiritual TV channel named Aastha. In 2001, the station sent talent scouts to look for new faces, said Ajit Gupta, at the time the chief executive of the firm that owned Aastha. They came across Mr. Ramdev.

“His language was straight. People were impressed by his stomach asanas,” a yoga position, Gupta said. The more slots the channel put Ramdev on, the more requests it received from viewers to see him, said Ved Sharma, then marketing manager at Aastha. Mr. Ramdev was becoming a star.

Today Ramdev is the public face of the company that he and Balkrishna founded, looking down from billboards across India. Aditya Pittie, who runs one of Patanjali's largest distributors, calls Mr. Ramdev the “super boss.” Yet current corporate filings make no mention of him. Mr. Ramdev's name did appear on a document published by the company on its website in 2011. Dated from 1999, it showed Mr. Ramdev signing as the president of one of the firm's trusts. Three years prior, his signature appeared on a balance sheet of the same trust. Mr. Ramdev told Reuters he'd given signing authority permission to sign on his behalf to Mr. Balkrishna.

At his office in Haridwar recently, Mr. Balkrishna sat at a desk with his back to an image of Mr. Ramdev in meditation. “We don’t have any planner,” he said, meaning an executive charged with corporate strategy. “We have swami-ji,” he said, referring to Mr. Ramdev.

Mr. Balkrishna pointed to the plain slippers on his feet. They had cost ₹400 (about $6), he said. Neither he nor Mr. Ramdev collect salaries, he added. Mr. Balkrishna's net worth was estimated at $2.5 billion last year by Forbes, making him the 48th richest Indian in a nation of some 1.3 billion people. Nothing is known publicly about Mr. Ramdev's assets.

A Reuters review of the financial filings of dozens of Patanjali companies found large dividend payments to Mr. Balkrishna, Mr. Ramdev's brother Mr. Ram Bharat and other owners. In one company, Mr. Balkrishna and minority shareholders received about $18 million in five years. In another company controlled by Mr. Ramdev's brother, dividends declared one year amounted to 60% of profits.

Mr. Balkrishna told Reuters that dividends were used to repay original investors: “I took money out of the company in the form of dividends to pay them. So today our company is neat and clean.”

Neither Mr. Ramdev's brother nor other company representatives responded to written questions about the dividend payments.

Into the political scene

Mr. Ramdev burst into politics in 2011 when he joined anti-corruption protests directed against the ruling Congress Party. In 2013, he made a series of public remarks backing Mr. Modi as the man to lead India. It was the beginning of a multi-pronged campaign by Mr. Ramdev in support of Mr. Modi, the full details of which have not previously been reported.

A communications firm called Social Revolution Media and Research Pvt Ltd was started by two directors from companies under the Patanjali umbrella, according to corporate filings. It held weekly meetings with the BJP's information technology division to coordinate messages on Twitter and other social platforms, said Shantanu Gupta, the communications firm's CEO.

Members of Mr. Ramdev's organization describe how hundreds of thousands of volunteers spread out to mobilise votes for Mr. Modi. In Mumbai, Narendra Shastri, a yoga teacher with a Patanjali trust, said he worked from dawn to dark, ringing doorbells and handing out pamphlets backing Mr. Modi's party.

Two days after the election results were announced, a pair of senior BJP leaders attended a stadium event in New Delhi to thank Mr. Ramdev and his volunteers. Both had signed the pledges shown in Mr. Ramdev's video earlier in the year.

On a different stage this May, at an inauguration ceremony for a Patanjali research institute in Haridwar, Mr. Modi clapped his hands in a gesture of respect toward Mr. Ramdev. Mr. Ramdev returned the gesture, tilting his head with a wide smile.

Modi proclaimed to the audience, and to those watching the live broadcast at home, “Baba Ramdev will take Bharat's ayurveda” — India's ancient medicine — “before the world.”