Ever since the board of Tata Sons Ltd, the holding company of the $100-billion Tata Group, sacked Cyrus Mistry as its chairman, both sides have been at loggerheads with each other and a full-fledged boardroom war has ensued.

Amid all the allegations and counter-allegations, Bharatiya Janata Party leader and Rajya Sabha member Subramanian Swamy waded into the controversy. The intrepid leader, who had earlier made several unsubstantiated allegations against former Reserve Bank of India governor Raghuram Rajan, said that Ratan Tata had been “the most corrupt chairman” in the group’s history and that he was “not even a Tata” as his father had been an adopted child.

Swamy’s motivations for riling against the corporate czar notwithstanding, the fact remains that the Tatas do have a rather complicated family tree that can flummox anyone. Here’s all you may want to know about Ratan Tata’s pedigree and how he came to dominate India’s largest conglomerate in the past two-and-a-half decades.

Who was Ratan Tata’s father? And was he a ‘real’ Tata?

Ratan Naval Tata was born to Naval Hormusji Tata and Soonoo Commissariat, his first wife. Naval, however, wasn’t born into the main Tata family. He was born in a middle class Parsi family in Bombay in 1904, to Hormusji Tata, a spinning mill master, who died when Naval was just four.

Despite the common surname, it is unclear if Hormusji was himself directly related to the wealthy Tata family that would later adopt his son. But he certainly wasn’t as wealthy.

Who was Naval’s mother?

Hirabai Daboo, the wife of Jamshedji Tata, who founded the Tata empire in the 19th century, had a sister Cooverbai Daboo. Cooverbai married Shapoorji Rao, with whom she had a daughter named Ratanbai Rao.

Ratanbai married Hormusji Tata and Naval was born to the couple in 1904. So, although Naval was later adopted by the Tata family, he wasn’t a rank outsider, as he was born to the niece of the group founder’s wife.

After Hormusji’s untimely demise, Ratanbai struggled to raise her children in Mumbai, and eventually shifted to Navsari in present day Gujarat. BC Pandey notes in his book, Business Kohinoor: Ratan Tata, how Naval’s mother made ends meet with her income from Zardosi. After a while, Naval and his siblings were sent off to the JN Petit Parsi orphanage in Surat.

So, did Naval’s fortunes turn for the better?

Yes, and it happened while he was still at the orphanage. Jamshedji Tata had two sons—Dorabji and Ratanji, neither of whom, Panday notes, had successors of their own. When Sir Ratan Tata died in 1918, he was just 47. It was then that the Tata family decided that for a ‘good sacrament’ they needed to adopt a son, who would succeed them. So, Sir Ratan Tata’s wife, Lady Navajbai (or Lady Tata, as she was known), adopted the young Naval.

Naval formally entered the Tata business in 1930 after completing his studies first at the Mumbai university and later in England.

When was Ratan Naval Tata born and who raised him?

Ratan Naval Tata was born in December 1937 to Naval Tata and his first wife Soonoo. He had a kid brother Jimmy, who too went on to hold senior positions at the Tata group.

After their parents separated sometime in the 1940s, Ratan and Jimmy were raised by their grandmother Navajbai.

Naval Tata re-married and Ratan's half-brother Noel Tata was born to his stepmother Simone Tata. Noel, who is also reportedly in the reckoning for the top job at Tata Sons, is married to Cyrus Mistry’s sister Aloo Mistry.

So, how did Ratan Tata rise to the helm at Tata Sons?

Ratan Tata began working for the Tata group in 1961. After three decades, he was chosen by the then chairman JRD Tata as his successor. In 1991, Ratan Tata became the chairman of Tata Sons and remained at the helm for 21 years.

How exactly were JRD Tata and Ratan Tata related?

Group founder Jamshedji Tata had an uncle (mother’s brother) named Dadabhoy Tata. He had one son, Ratanji Dadabhoy Tata, who became one of the partners in Tata Sons.

Jehangir Ratanji Dadabhoy (JRD) Tata was the second of Ratanji’s five children from his second wife, a Frenchwoman Suzanne Briare.

So, although JRD Tata and Ratan Tata come from two different branches of the Tata family, the former mentored the latter, and handed him the baton in 1991.

Is Cyrus Mistry related to the Tatas?

Not directly, but his sister Aloo Mistry is married to Noel Tata, Ratan Tata’s half-brother. The Mistry family has, however, had business relations with the Tatas since the 1930s when they began buying stakes in Tata Sons, and are now the largest shareholders in the holding company, apart from the Tata trusts themselves.

What is Nusli Wadia’s connection to the Tatas?

This is slightly more complicated. Ratanji Dadabhoy Tata had a maternal granddaughter Rattanbai ‘Ruttie’ Petit, who was the second wife of Mohammad Ali Jinnah, the founder of Pakistan. Although Ruttie died early, she had a daughter Dina, who chose to stay back in India, when the country was partitioned in 1947.

Dina Jinnah went on to marry Neville Wadia, and the couple had a son Nusli, who would go on to succeed his father as the head of the Wadia group.

Interestingly, as VCCircle noted earlier this month, Nusli was close to JRD Tata, who had helped him thwart his

father’s plans to sell Bombay Dyeing to industrialist RP Goenka. In the present imbroglio, Nusli, an independent director on several Tata group companies, has joined forces with Mistry, and is opposing his ouster.

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