Somalis in Ethiopia refers to the ethnic Somalis from Ethiopia, particularly the Ogaden, officially known as the Somali Region. Their language is primarily Somali and are predominantly Muslim. According to the 2007 census from the Central Statistical Authority, the Somalis were the third largest ethnic group in Ethiopia with roughly 4.6 million people accounting for 8.2% of the country's population, after Oromo (34.4%) and Amhara (27%). The Somali population in Ethiopia make up around 30% of the total Somali population worldwide.

Somalis have inhabited the interiors of the Horn for thousands of years. According to linguists, the first Afro-Asiatic-speaking populations arrived in the region during the ensuing Neolithic period from the family's proposed "Urheimat" (Original Homeland) in the Nile Valley, or Near East. Other scholars propose that the Afro-Asiatic family developed in the Horn of Africa, with its speakers subsequently dispersing from there.

Islam was introduced to the area early on by the first Muslims of Mecca fleeing prosecution during the first Hejira with Masjid al-Qiblatayn being built before the Qiblah faced towards Mecca. The town of Zeila's two-mihrab Masjid al-Qiblatayn dates to the 7th century, and is one of the oldest mosques in Africa. Consequently, the Somalis were some of the earliest non-Arabs to convert to Islam.

The first clear written Ethiopian reference of the ethnonym Somali dates back to the early 15th century during the reign of Ethiopian Emperor Yeshaq I who had one of his court officials compose a hymn celebrating a military victory over the Sultanate of Ifat. Simur was also an ancient Harari alias for the Somali people.

Somalis began building nation-state networks to various states in the form of sultanates. The Adal Sultanate (ruled by the Somali Muslims with other signification Cushitic Muslim populations like Hararis and Afars) was one of the most powerful states with capital Zeila (in present-day Somalia).

In response to centuries of mistreatment by the Ethiopian Empire, the 16th century Imam Ahmad ibn Ibrahim al-Ghazi united the Muslims of the Horn of Africa, and led an invasion of Abyssinia which brought much of the Christian polity under Muslim control. The Ethiopians, as a last resort managed to secure the assistance of the Portuguese Empire and maintained their domain's autonomy, defeating Imam Ahmad at the Battle of Wayna Daga.

There is no evidence that Ethiopia controlled any Somali inhabited territory at any point in history prior the Menelik's Expansions to south and south-east in the late 19th century. Rather independent historical accounts are unanimous that prior to Ethiopian penetration into the Ogaden and Hararghe in the late 1880s, Somali clans were free of Ethiopian and Shewan control. In 1884, during the Scramble for Africa, a vast land of Somalia fell under three colonial domains: the British protectorate of Somaliland was established through a number of Anglo-Somali Treaties of Protection. In the same manner, the Italians took direct claims of Italian Somalia and its coast in 1889. This was resolved in 1891 Anglo-Italian Treaty with British colonial powers on their sphere of influence in the East Africa (mainly Ethiopia, Somalia, and Eritrea).

In accordance with Treaty of Wuchale (1889) signed between Ethiopia and Italy, Italy, acting as protector of Ethiopia, demarcated the boundary between Ethiopia and British Somaliland as follows:

The boundary of the spheres of influence of Great Britain and of Italy in the regions of the Gulf of Aden shall be constituted by a line which, starting from Gildessa [Jeldesa] and running toward the eighth degree of north latitude, skirts the north-east frontier of the territories of the Girrhi, Bertiti, and Rer Ali Tribes, leaving to the right the villages of Gildessa, Darmi, Gig, and Milmil. On reaching the eighth degree of the north latitude the line follows that parallel as far as its intersection with the 48th degree of longitude east of Greenwich.

Ignoring the Anglo-Italian Treaty that laid foundation of Gadabuursi clan land under British protectorate, Menelik attempted and penetrated Somali territory in 1896 by building some grass hits at Alola, a spring located in the southeast of Biyo Kabobe. Menelik erected flag by claiming Gadabuursi and Issa clan's territories (in present-day Shinile, Jijiga to Awbare) belongs to the Ethiopian Empire.

Menelik proposed boundary extension of his Empire to Western Somali territories of Ogaden and submitted to Italy on 24 June 1896, and one year later. Italy unilaterally agreed its boundaries by only telegraphing without proper agreement. In 1897, the Ethiopian Empire continued its expansion territories of the south and southeast where Somali people settled, reached an agreement with the British to demarcate border between Ethiopia and British Somaliland, excluding Haud in Ethiopia. In the treaty, British ceded Somali territory to the Menelik in exchange for his help fighting against Somali clans. However, the treaty occurred when Ethiopia, the British administration and Somali people were not consulted and informed. In addition, the treaty violated an agreement between the British and Somali clans in which it was one of the main reasons that Somali's denied the validity of the treaty.

In 1907, Anglo-Ethiopian Agreement demarcated their boundary with the British East African protectorate (Kenya). This placed Italian Somaliland in a rectangular point where Dewa and Genale rivers conjoin.

In December 1934, the Welwal incident was erupted in Welwal located in Dollo Zone of the Somali, as the beginning of the Second Italo-Ethiopian War and Italian occupation of Ethiopia. During an occupation, the British Somaliland annexed to Italian East Africa to Haud and Ogaden region. From this point, Italy promoted and initiated the idea of "Greater Somalia", constituting Somali settled territories. By September 1940, Benito Mussolini declared the formation of Greater Somalia into the Italian Empire.

In 1941, the British entered the Italian Somaliland, Haud and Ogaden with the help of Ethiopian armies. Soon after the restoration of Haile Selassie rule, the Haud and Ogaden region immediately placed under British military administration until Anglo-Ethiopian Agreement of 1942 warranted its sovereignty status in 1944. The first Somali nationalist group was emerged in May 1943 called Somali Youth Club (later renamed SYL) by thirteenth young Somali nationalist operating its field offices in Ogaden region, particularly in Jijiga and Kenya.

In 1946, the British foreign secretary, Ernest Bevin, proposed to the Allied Council of Foreign Ministers a plan to place the Somali-inhabited territories under the British Military Administration. Unfortunately the Bevin Plan was rejected and the Soviet Union, United States and France blatantly stood against that plan. In 1948, the British administration withdrew from Ogaden and without formal concession using secret agenda, the British handed the region to Ethiopia. Thus, the modern Somali Region united to Ethiopia. In 1955, the British administration withdrew from the Haud and the Reserved Area, and Ethiopia took all over the territories. In March 1955, the National United Front (NUF) attempted to retake the Haud and the Reserved Area and to end the Somalia rule under British protectorate, culminating in series violent clashes and conflicts.

In 1958, the UN Trusteeship Council appointed arbitration tribunal for the disputed territories between Ethiopia and Somalia with futile effort. Somalia constantly denied the Anglo-Ethiopian delimitation of 1897 and provided no legal recognition. In 1948 and 1954 discontent led to liberate and cede the Greater Somalia and subsequently denied the validity of Anglo-Ethiopian Agreement of 1897.

Following Somalia's independence in 1960, its successive government launched campaign what they called "lost territories" and raised the issues to regional and international communities like the United Nations and Organization of Islamic countries. Consecutive governments of Somalia attempted to incorporate the regions and established the Somali Republic to achieve Greater Somalia. The hostility between Ethiopia and Somalia relations grew faster, even garnered international interests involving Somali pastoralists and Ethiopian police forces in the region. In February 1964, a brief war was started in the border until Sudan mediates in front of Organization of African Unity. Minister from both sides met in Khartoum to announce ceasefire with 15 km military withdrawal from both sides.

In 1966, Ethiopia suspended martial law in the Somali Region and neighboring Oromo region accompanied by shocking retribution against herders to force them renounce their support for the fighters. Many of these were applied through confiscation, arbitrary arrests, to control water points and destroying their livestock.

In 1973, Western Somali Liberation Front (WSLF) was established and recruit reluctant inhabitants of the region. Somalia supported WSLF, Somali Abo Liberation Front (SALF) and Oromo Liberation Front (OLF) to weaken the Ethiopian forces in the region as well to destabilize the country. In 1977, large-scale war launched known as Ogaden War after Somali National Army crossed the border into Ethiopia and carried out military operations in Degehabur, Kebri Dahar, Warder and Godey taking control of Jijiga and other western region in the first few weeks of the war. The Soviet Union, Cuba, and South Yemen supported Ethiopia's Derg government led by Colonel Mengistu Haile Mariam and force Somali troops back to the area occupied and led to weakening the government. In March 1978, Siad Barre recalled his army from Ethiopia.

After the Derg collapse, many Somalis returned to Ethiopia in May 1991 after they evacuated in 1960s. Some of these were senior military leaders and political entrepreneurs to form the Ethiopian People's Revolutionary Democratic Front (EPRDF). In 1994, new constitution was drafted marked with the creation of Somali Region drawn to other regions.

With a staggering population of over 4.6 million almost all of the major Somali clan families are represented in Ethiopia. The Issa and Gadabuursi subclans of the Dir primarily inhabit the northern Sitti zone and the Awbare woreda in Fafan zone.

The Habr Awal, Garhajis, Habr Je'lo and Arap clans of the Isaaq clan family inhabit the northern part of the region bordering Somaliland. The Habr Awal primarily inhabit the Fafan zone making up the majority in Harshin woreda as well as making up a significant portion of the population of the Kebribeyah woreda as well as the lucrative towns of Wajaale and Hart Sheik. The Garhajis and Habr Je'lo make up the majority of Awaare and Misrak Gashamo woredas in Jarar zone with a significant presence in the Danot woreda.

Subclans of the Hawiye inhabit the western and southern areas of the region, with large presence of Degodia being majority in Liben and significant presence in some regions. Karanle and Sheekhaal present in the western areas bordering the Oromia region and the Hawadle and Habar Gidir subclans are present in the Shabelle zone. The closely related Samaale subclan of Garre are also present in the Liben zone and Dawa zone where they make up the majority.

Various subclans of the Darod clan family primarily inhabit the central and eastern parts of the region, with the Ogaden and Jidwaq inhabiting the interior as well as the major towns of Jijiga, Gode, Kebridehar. The Harti as well as the Leelkase clans inhabit the Dollo zone where they make up the majority while the Marehan clan inhabit the Shilavo woreda and the Liben zone.

In 2009, Ethiopia had an estimated 135,000 asylum seekers and refugees, mostly from Somalia (64,000).

• Somali Region in Ethiopia: Historical Developments during the Period 1884-1995

• FitzGibbon, Louis (1985). The Evaded Duty. London: Rex Collings. ISBN 0860362094. OCLC 15018961.