The 1964 Ethiopian–Somali Border War, also known as the First Ogaden War marked the first military conflict between the newly established Somali Republic and the Ethiopian Empire, lasting from February to April 1964. The border conflict was preceded by a rebellion in Ethiopia's Ogaden region, inhabited primarily by the Ogaden and other Somali clans, which began in mid-1963, shortly after Somalia's independence and unification of the two Somaliland colonies. Irredentist ambitions towards achieving further unity in the form of Greater Somalia led to encouragement and support for the Ogaden insurgency. The subsequent suppression of insurgents and increasingly harsh reprisals carried out by Emperor Haile Selassie's government resulted in a rapid decline in Ethio-Somali relations, eventually leading to direct confrontation between both governments' armed forces.

Ethiopia–Somalia relations are bilateral relations between Ethiopia and Somalia. These relations are characterized by the land border shared by the two countries and a number of military conflicts in past years.