Power last changed hands 18 years ago in the Democratic Republic of Congo, sub-Saharan Africa's largest country by area and third-largest by population, when Laurent Kabila was assassinated and his son Joseph took office at the age of 29. That was during the Second Congo War (1998-2003), the world's deadliest conflict since World War Two.
Flash forward: After two years of delay, national elections will be held on December 23. Kabila has said he'll respect constitutional term limits and step aside. He endorsed a loyalist to succeed him.