Answer
Omar Bongo, who served as the president of Gabon from 1967 to 2009, had the longest reign of any non-royal leader since 1900. During his 42-year tenure, Bongo oversaw the development of Gabon’s oil industry and transformed the country into one of the wealthiest in sub-Saharan Africa. However, he was also criticized for corruption, human rights abuses, and nepotism.