Somali guerrilla activity in the Ogaden and in the Haud area east of Harer flared sporadically after Somalia gained its independence in 1960, but the guerrilla activity remained essentially a police concern until a border war erupted in 1964. When he seized power in Mogadishu in 1969, Siad Barre thwarted attempts at an understanding between Ethiopia and Somalia. He pledged to renew efforts to establish a "Greater Somalia" that would encompass about one-third of Ethiopia's territory. Encouraged by the breakdown of authority in Addis Ababa after the 1974 overthrow of Haile Selassie, Somalia provided matériel, moral, and organizational support to insurgent movements in the Ogaden and southern Ethiopia.
The Western Somali Liberation Front (WSLF), which operated in the Ogaden, supported the "Greater Somalia" concept. The Somali Abo Liberation Front (SALF) maintained links to the WSLF. Its sphere of operations was in Bale, Sidamo, and Arsi, where it advocated union with Somalia or the creation of an independent state. Somalia equipped both groups with Soviet arms; both also received aid and training from various Arab and communist nations, including Cuba.
After the 1977-78 Ogaden War, the WSLF was routed, and its troops flocked to camps in Somalia. The Somali government subsequently forbade the WSLF to use its territory to launch attacks into Ethiopia. By 1989 the WSLF had ceased to be an effective guerrilla organization within Ethiopia. Siad Barre´s decision to restrict the WSLF led to the formation of a WSLF splinter group, the Ogaden National Liberation Front (ONLF), whose headquarters were in Kuwait. Elements of the ONLF slipped back into the Ogaden in 1988 but failed to generate a significant military capability.
Somali resistance to their colonial masters, both familiar and foreign, began in 1899 under the leadership of religious scholar Sayyid Mohammed Abdullah Hassan, Ogaden sub-lineage of the Darod tribe and his mother was Dulbahante sub-lineage of the Darod tribe.
Somali's internal disputes were manifested outwards in hostility to Ethiopia and Kenya, which they felt were standing in the way of 'Greater Somalia'.
The Somalis however were increasingly becoming jaded of the United States, which had been sending substantial military aid to their hostile neighbor, Ethiopia, and thanks to incessant anti-Western indoctrination at the hands of their new Russian friends.
A significant impetus to the Somali nationalist movement was provided by the UN in 1949 when the General Assembly resolved that Italian Somaliland would receive its independence in 1960.
From the inception of independence, the Somali government supported the concept of self-determination for the people of the Somali-inhabited areas of Ethiopia (the Ogaden section), Kenya (most of the northeastern region), and French Somaliland (now the Republic of Djibouti), including the right to be united within a greater Somalia.
Somali forces took part in the fighting but were defeated in 1977, soon after the USSR had swung its support to Ethiopia.