Horn of Africa displays the greatest diversity, a sign often viewed to represent a geographic origin. The Horn of Africa is also the place where the haplogroup E1b1b originated from, Christopher Ehret and Shomarka Keita have suggested that the geography of the E1b1b lineage coincides with the distribution of the Afroasiatic languages. Genetic analysis done on the Afroasiatic speaking population further found that a pre-agricultural back-to-Africa migration into the Horn of Africa occurred through Egypt 23,000 years ago and it brought a non-African ancestry dubbed Ethio-Somali in the region. Together with northern Somalia, Djibouti, the Red Sea coast of Sudan and Eritrea is
Horn of Africa as የአፍሪካ ቀንድ yäafrika qänd in Amharic, القرن الأفريقي‎ al-qarn al-'afrīqī in Arabic, Gaaffaa Afriikaa in Oromo and ቀርኒ ኣፍሪቃ in Tigrinya. The Horn of Africa is sometimes shortened to "HOA". The Horn of Africa is quite commonly designated simply the "Horn", while inhabitants are sometimes colloquially referred to as "Horn Africans". Sometimes the term "Greater Horn of Africa" is used, either to be inclusive of neighbouring northeast African countries, or to distinguish the broader geopolitical definition of the Horn of Africa from narrower peninsular definitions. Ancient Greeks and Romans referred to the Somali peninsula as Regio Aromatica or Regio