Landmark is level 2 of 4 in the Nigeria Hall of Fame: a first that opened a door, or the pre-eminent figure of their generation in this country. See how the levels work.
Why they are here
A zoologist from Bayelsa State who became president on the death of Umaru Musa Yar'Adua and won the 2011 election.
In 2015 he conceded defeat to Muhammadu Buhari before the final results were announced, allowing the first peaceful transfer of power to the opposition.
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