[8][9][10] It has been described as a region of geopolitical and strategic importance, since it is situated along the southern boundary of the Red Sea; extending hundreds of kilometres into the Gulf of Aden, Guardafui Channel, and Indian Ocean, it also shares a maritime border with the Arabian Peninsula.
[33] The findings of the Earliest Stone Tipped Projectiles from the Ethiopian Rift dated to more than 279,000 years ago "in combination with the existing archaeological, fossil and genetic evidence, isolate East Africa as a source of modern cultures and biology.
Somali sailors and merchants were the main suppliers of frankincense, myrrh and spices, all of which were valuable luxuries to the Ancient Egyptians, Phoenicians, Mycenaeans, Babylonians and Romans.
In the classical era, several flourishing Somali city-states such as Opone, Mosylon and Malao also competed with the Sabaeans, Parthians and Axumites for the rich Indo-Greco-Roman trade.
[45] The birth of Islam opposite the Horn's Red Sea coast meant that local merchants and sailors living on the Arabian Peninsula gradually came under the influence of the new religion through their converted Arab Muslim trading partners.
Through a strong centralized administration and an aggressive military stance towards invaders, the Ajuran Sultanate successfully resisted an Oromo invasion from the west and a Portuguese incursion from the east during the Gaal Madow and the Ajuran-Portuguese wars.
Trading routes dating from the ancient and early medieval periods of Somali maritime enterprise were also strengthened or re-established, and the state left behind an extensive architectural legacy.
The royal family, the House of Gareen, also expanded its territories and established its hegemonic rule through a skillful combination of warfare, trade linkages and alliances.
In 1270, the Amhara nobleman Yekuno Amlak, who claimed descent from the last Aksumite king and ultimately the Queen of Sheba, overthrew the Agaw Zagwe dynasty at the Battle of Ansata, ushering his reign as Emperor of Ethiopia.
While initially a rather small and politically unstable entity, the empire managed to expand significantly during the crusades of Amda Seyon I (1314–1344) and his successors, becoming the dominant force in East Africa.
[60][61] During the end of 18th and the beginning of 19th century the Yejju dynasty (more specifically, the Warasek) ruled north Ethiopia changing the official language of Amhara people to Afaan Oromo, including inside the court of Gondar which was capital of the empire.
[74] In the period following the opening of the Suez Canal in 1869, when European powers scrambled for territory in Africa and tried to establish coaling stations for their ships, Italy invaded and occupied Eritrea.
The lack of regard for the Eritrean population led to the formation of an independence movement in the early 1960s (1961), which erupted into a 30-year war against successive Ethiopian governments that ended in 1991.
[78] From 1862 until 1894, the land to the north of the Gulf of Tadjoura situated in modern-day Djibouti was called Obock and was ruled by Somali and Afar Sultans, local authorities with whom France signed various treaties between 1883 and 1887 to first gain a foothold in the region.
The referendum favoured continued association with France, partly due to a combined yes vote by the sizable Afar ethnic group and resident Europeans.
[83] The majority of those who voted no were Somalis who were strongly in favour of joining a united Somalia, as had been proposed by Mahmoud Harbi, Vice President of the Government Council.
Italy faced similar opposition from Somali Sultans and armies, and did not acquire full control of modern Somalia until the Fascist era in late 1927.
[89] In 1991, the Somali Civil War broke out, which saw the dissolving of the union and Somaliland regaining its independence, along with the collapse of the central government and the emergence of numerous autonomous polities, including the Puntland administration in the north.
[90] Somalia's inhabitants subsequently reverted to local forms of conflict resolution, either secular, Islamic or customary law, with a provision for appeal of all sentences.
[100] Haile Selassie subsequently appealed to the League of Nations, delivering an address that made him a worldwide figure and 1935's Time magazine Man of the Year.
[101] Following the entry of Italy into World War II, British Empire forces, together with patriot Ethiopian fighters, liberated Ethiopia during the East African Campaign in 1941.
By September 1977, the Somali army controlled 90 percent of the Ogaden, but was later forced to withdraw after Ethiopia's Derg received assistance from the USSR, Cuba, South Yemen, East Germany[103] and North Korea, including around 15,000 Cuban combat troops.
It consists chiefly of mountains uplifted through the formation of the Great Rift Valley, a fissure in the Earth's crust extending from Turkey to Mozambique and marking the separation of the African and Arabian tectonic plates.
In the winter, the northeasterly trade winds do not provide any moisture except in mountainous areas of northern Somalia, where rainfall in late autumn can produce annual totals as high as 500 mm (20 in).
The endangered painted hunting dog had populations in the Horn of Africa, but pressures from human exploitation of habitat along with warfare have reduced or extirpated this canid in this region.
For centuries, the region's pastoral groups have observed careful rangeland management practices to mitigate the effects of drought, such as avoiding overgrazing or setting aside land only for young or ill animals.
[113] As of 2023, the Horn of Africa is affected by a severe ongoing drought and famine that has been going on for six consecutive years, especially in Somalia and in the months from March to May during which 60 percent of the annual rainfall occurs.
Besides sharing similar geographic endowments, the countries of the Horn of Africa are, for the most part, linguistically and ethnically linked together,[21] evincing a complex pattern of interrelationships among the various groups.
These tongues include the Nilo-Saharan Me'en and Mursi languages used in southwestern Ethiopia, and Kunama and Nara idioms spoken in parts of southern Eritrea.
In the riverine and littoral areas of southern Somalia, Bajuni, Barawani, and Bantu groups also speak variants of the Niger-Congo Swahili and Mushunguli languages.