Ethiopia’s Great Rift Valley is the origin of human civilization, according to anthropologists, with skeletal remains of prehistoric man dating back 3.5 million years and evidence of language systems as early as 13000 B.C. discovered there. There is also evidence of animal domestication, sophisticated agricultural techniques and influence of people migrating from across the Red Sea dating back at least several thousand years before the Christian era.
Names for Ethiopia throughout history include Nubia, Kush and Abyssinia. Ethiopia became the second nation to adopt Christianity, after Armenia, in 324 A.D. Between 325 and 1700, control of Ethiopia changed hands between Muslin, Coptic and Roman Catholic rulers, often with European, Ottoman and Arab supporters. Ethiopia successfully defended invasions by Turkey, Egypt, Sudan and Italy under the reign of Menelik II between 1879 and 1913.
Haile Selassie became the de facto emperor in 1916 until being deposed by Communist-backed rebels in 1974. Selassie's appeal to the League of Nations following the 1935 invasion of Ethiopia by Italian forces under Mussolini drew worldwide attention to the expansion of European Fascism and earned him recognition as Time magazine's Person of the Year. In 1942, Selassie abolished slavery, freeing between two to four million slaves in a country of 11 million people.
The turmoil following the collapse of Selassie’s rule and constant conflicts with Eritrea, Somalia and other regional powers led to a series of famines during the 1980s in which at least one million people died. The Communist regime, faced with constant opposition, fled in 1991 after the refusal of the Soviet Union to continue aid. A semi-constitutional form of government replaced it and still exists, as of 2015.