It's actually difficult to give 3 major events because the most important events in modern history are closely tied together.
But, if you mean "events" more than "periods of time", then 3 major events related to/in Nigeria would be:
Nigerian bus electrocutions happened in 2010.
Nigerian Sharia conflict happened on 1953-05-01.
yes, I happen to go to one apostolic Nigerian church right now.
Lassic happened in 1861.
1850 - 1860
It occurred on April 1861.
it happen at charleston harbor, south carolina april 12 1861
July 21st 1861
It occurred on April 1861.
April 12th 1861.
Larut War happened in 1861.
Battle of Pavón happened in 1861.