Formerly Known as Abyssinia
Ethiopia, country on the Horn of Africa. The country lies completely within the tropical latitudes and is relatively compact, with similar north-south and east-west dimensions. The capital is Addis Ababa (“New Flower”), located almost at the centre of the country. Ethiopia is the largest and most populated country in the Horn of Africa. With the 1993 secession of Eritrea, its former province along the Red Sea, Ethiopia became landlocked.
Ethiopia is one of the world’s oldest countries, its territorial extent having varied over the millennia of its existence. In ancient times it remained centred on Aksum, an imperial capital located in the northern part of the modern state, about 160 km from the Red Sea coast. The present territory was consolidated during the 19th and 20th centuries as European powers encroached into Ethiopia’s historical domain.
Ethiopia became prominent in modern world affairs first in 1896, when it defeated colonial Italy in the Battle of Adwa, and again in 1935–36, when it was invaded and occupied by fascist Italy, but never colonized. Liberation during World War II with the help of Allied powers set the stage for Ethiopia to play a more prominent role in international proceedings.
Ethiopia was among the first independent nations to sign the Charter of the United Nations, and it gave moral and material support to the decolonization of Africa and to the growth of Pan-African cooperation. These efforts climaxed in the establishment of the Organization of African Unity (since 2002, the African Union) and the United Nations Economic Commission for Africa, both headquartered in Addis Ababa.
Ethiopia’s terrain, one of the most rugged in Africa, built on four geologic formations. Rocks of Precambrian origin (more than 540 million years in age) form the oldest foundational complex of Ethiopia, as they do in most of Africa. The Precambrian layer is buried under more recent geologic formations—except in parts of northern, western, and southern Ethiopia, where there are exposed rock layers of granite and schist. Rock-like formations of the Mesozoic Era (about 250 to 65 million years ago) contributed sedimentary layers of limestone and sandstone, most of which have been either eroded or covered by volcanic rocks.
Younger dense layers are found in northern Ethiopia and on the floors of the Rift Valley. Lava flows from the Cenozoic Era (i.e., the past 65 million years) have formed basaltic layers that now cover two-thirds of Ethiopia’s land surface with a thickness ranging from about 1,000 feet (300 metres) to almost 10,000 feet (3,000 metres). The Rift Valley forms a incredible depression (a massive tectonic trough) running right down the middle of the country from the northern frontier with Eritrea to the southern border with Kenya.
Although Ethiopia’s complex defies easy classification, five topographic features are discernible. These are the Western Highlands, the Western Lowlands, the Eastern Highlands, the Eastern Lowlands, and the Rift Valley. The Western Highlands are the most extensive and rugged topographic component of Ethiopia. The most amazing section is the North Central massifs; these form the roof of Ethiopia, with elevations ranging from 14,872 feet (4,533 metres) for Mount Ras Dejen (or Dashen), the highest point in Ethiopia, to the Blue Nile and Tekeze river channels 10,000 feet below. Lake Tana—Ethiopia’s largest inland lake and the main reservoir for the Blue Nile River—is located in this region, at an elevation of about 6,000 feet (1,800 metres).
The Western Lowlands stretch north-south along the border with Sudan and South Sudan and include the lower valleys of the Blue Nile, Tekeze, and Baro rivers. With elevations of about 3,300 feet (1,000 metres), these lowlands become too hot to attract dense settlement.
The Rift Valley is part of the larger East African Rift System. Hemmed in by the escarpments of the Western and Eastern Highlands, it has two distinct sections. The first part is in the northeast, where the valley floor widens into a funnel shape as it approaches the Red Sea and the Gulf of Aden. This is a relatively flat area interrupted only by occasional volcanic cones, some of which are active. The Denakil Plain, in which a depression known as the Kobar Sink drops as low as 380 feet (116 metres) below sea level, is found here. High temperatures and small amounts of moisture make the northeastern Rift Valley unattractive for settlement. The southwestern section, on the other hand, is a narrow depression of much higher elevation. It contains Ethiopia’s Lakes Region, an internal drainage basin of many small rivers that drain into Lakes Abaya, Abiyata, Awasa, Langano, Shala, Chamo, and Ziway. Together these lakes have more than 1,200 square miles (3,108 square km) of water surface. The upper Rift Valley is one of the most productive and most settled parts of Ethiopia.
The Eastern Highlands are much smaller in extent than the Western Highlands, but they offer equally impressive contrast in topography. The highest peaks are Tullu Deemtu (Tulu Dīmtu), at 14,360 feet (4,377 metres), and Mount Batu, at 14,127 feet (4,305 metres). The Eastern Lowlands resemble the long train of a bridal gown suddenly dipping from the narrow band of the Eastern Highlands and gently rolling for hundreds of miles to the Somalian border. Two important regions here are the Ogaden and the Hawd. The Shebele and Genale rivers cross the lowlands, moderating the desert ecology.
Because Ethiopia is located in the tropical latitudes, its areas of lower elevation experience climatic conditions typical of tropical savanna or desert. However, relief plays a significant role in moderating temperature, so higher elevations experience weather typical of temperate zones. Thus, average annual temperatures in the highlands are in the low 60s F (mid-10s C), while the lowlands average in the low 80s F (upper 20s C).
There are three seasons in Ethiopia. From September to February is the long dry season known as the bega; this is followed by a short rainy season, the belg, in March and April. May is a hot and dry month preceding the long rainy season (kremt) in June, July, and August. The coldest temperatures generally occur in December or January (bega) and the hottest in March, April, or May (belg). However, in many places July has the coldest temperatures because of the moderating influence of rainfall.
Ethiopia can be divided into four rainfall regimes. Rain falls year-round in the southern portions of the Western Highlands, where annual precipitation may reach 80 inches (2,000 mm). Summer rainfall is received by the Eastern Highlands and by the northern portion of the Western Highlands; annual precipitation there may amount to 55 inches (1,400 mm). The Eastern Lowlands get rain twice a year, in April–May and October–November, with two dry periods in between. Total annual precipitation varies from 20 to 40 inches (500 to 1,000 mm). The driest of all regions is the Denakil Plain, which receives less than 20 inches (500 mm) and sometimes none at all.