Ratan Tata grew up in the lap of luxury at a villa in the centre of Mumbai, parts of which went on to become Sterling Cinema and Deutsche Bank. In comparison, his current lifestyle is almost spartan.

For years, he has been living in the same flat in Colaba. Numerous executives and even first generation entrepreneurs lead more lavish lives. JRD Tata, while not exactly ostentatious, lived in a Cumbala Hill bungalow.

During the 10 years that he spent in the US, Tata took up all kinds of jobs, including washing dishes, to make ends meet. The dollars mandated by the Reserve Bank were not enough. In an interview two years ago, Tata, a bachelor, admitted to being lonely and "too diffident to do anything about it".

He is not where he is by design. Having studied architecture at Cornell University and management at Harvard, he may have remained an architect, regardless of his surname. But his grandmother fell very ill and he kept coming back to India to see her. One thing led to another and he stayed back.

Tata keeps away from Mumbai's party circuit, dresses conservatively, and gets to work early in either his black Mercedes or Tata Indigo, sitting beside his driver. Who would have thought this understated man of impeccable manners, who readily sacrificed an airline venture at the altar of government policy, would upset the global corporate order to such an extent? And so often?

It's tempting to forget that Tata is the same man who had been written off after he supervised the wind-up of Nelco, the radio making company of the group. He was not given a chance in hell when he took over as the chairman of Tata Sons in 1991, when the likes of Russi Mody and Ajit B Kerkar ran their own fiefdoms. And was nearly ridiculed when he invested over Rs 1,500 crore (Rs 15 billion) in a passenger car foray.

When he took charge of the group, 5 per cent of its turnover came from overseas. This rose to 20 per cent in 2002-03, mainly due to TCS emerging as a global force.

In 2005-06, the figure grew to 30 per cent. The acquisition of Corus will take the total group revenue to $41.87 billion, 63 per cent of which - $26.54 billion - will come from overseas.

The overseas drive of the group has been accompanied by a change in Tata, the person, too. The man has admitted in print to "issues" of "self consciousness" and "self confidence" early on. Some say the "issues" began to get resolved with the turnaround of Tata Motors in the new millennium.

The Corus deal comes when the dust has yet to settle down on Tata Tea's acquisition of 30 per cent equity in New York-based Glaceue for $677 million in August last year, and Tata Coffee's acquisition of Eight O' Clock Coffee of the US for $220 million in June.

Since its first high-decibel acquisition of UK tea company Tetley for $407 million in February 2000, the Tata Group has no less than 21 acquisitions under its belt.