Nigeria, Sept. 25 -- There is a nickname that has followed Michael Adeniyi Agbolade Ishola Adenuga Jr for decades: the Bull. It is more than a colourful tag attached to one of Nigeria's most successful businessmen. It has become a fitting metaphor for a career marked by persistence, audacity and an unusual willingness to enter difficult territory. Perhaps the best way to understand the Bull is to begin with a setback.

In 1999, Adenuga's company was among those awarded a GSM licence during Nigeria's first telecommunications licensing process. The licence was subsequently revoked. The setback did not end his interest in telecommunications. He returned to the race, bidding for the Second National Operator licence in 2002 through Globacom. T...