Horn of Africa, region of eastern Africa. It is the easternmost extension of African land and for the purposes of this article is defined as the region that is home to the countries of Djibouti, Eritrea, Ethiopia, and Somalia, whose cultures have been linked throughout their long history. Other definitions of the Horn of Africa are more restrictive and exclude some or all of the countries of Djibouti, Eritrea, and Ethiopia. There are also broader definitions, the most common of which include all the countries mentioned above, as well as parts or all of Kenya, Sudan, South Sudan, and Uganda. Part of the Horn of Africa region is also known as the Somali peninsula; this term is typically used when referring to lands of Somalia and eastern Ethiopia. The Horn contains such diverse areas as the highlands of the Ethiopian Plateau, the Ogaden desert, and the Eritrean and Somalian coasts and is home to the Amhara, Tigray, Oromo, and Somali peoples, among others. Its coasts are washed by the Red sea, the Gulf of Aden, and the Indian Ocean, and it has long been in contact with the Arabian Peninsula and southwestern Asia.