Festus Mogae, Botswana’s former president, has died at the age of 86, the government announced, declaring three days of national mourning.Mogae served as Botswana’s third president from 1998 to 2008, handing over power to his vice president, Ian Khama, in a smooth transition that reinforced the southern African nation’s reputation for political stability.An economist by training, Mogae was praised for his effective management of Botswana’s economy. He also confronted HIV/AIDS openly at a time when the country had one of the world’s highest infection rates, introducing one of Africa’s most comprehensive programmes to fight the disease.Born in Serowe on August 21, 1939, Mogae studied in Britain before joining Botswana’s civil service shortly after independence in 1966. He later served as finance minister and vice president before becoming president.Mogae retired after serving the constitutional limit of two terms.