What major change took place in Nigeria in 1999?

A civilian being elected as president was the major change took place in Nigeria in 1999.

Presidential elections were held in Nigeria on 27 February 1999. These were the first elections since the 1993 military coup, and the first elections of the Fourth Nigerian Republic. The result was a victory for Olusegun Obasanjo of the People's Democratic Party, who defeated Olu Falae, who was running on a joint Alliance for Democracy-All People's Party ticket.