The first Somali state to be granted its independence from colonial powers was Somaliland, a former British protectorate that gained independence on 26 June 1960. The rest of what came to be known as Somali Republic was under Italian rule under the title Trust Territory of Somaliland (also known as Somalia Italiana). Shortly after Somaliland gained independence, it was to form a hasty union with its southern neighbour to create the Somali Republic. Henceforth British Somaliland was referred to as the northern (or north western) region of the Somali Republic, whilst the former Italian colonial state was referred to as the south.
Within British Somaliland the Isaaq constituted the majority group within the protectorate with Dir and Harti groups also having sizeable populations to the west and east of Isaaq respectively.
The Isaaq genocide (Somali: Xasuuqii beesha Isaaq; Arabic: الإبادة الجماعية لقبيلة إسØاق), also known as the Hargeisa Holocaust, was the systematic, state-sponsored genocide of Isaaq civilians between 1987 and 1989 by the Somali Democratic Republic, under the dictatorship of Siad Barre, during the Somaliland War of Independence. The number of civilian deaths in this massacre is estimated to be between 50,000 and 100,000, according to various sources, whilst local reports estimate the total civilian deaths to be upwards of 200,000 Isaaq civilians. The genocide, which escalated after the Somali National Movement (SNM)'s 1988 Northern Somalia offensive, also included the levelling and complete destruction of the second and third largest cities in the Somali Republic, Hargeisa (which was 90 percent destroyed) and Burao (70 percent destroyed), respectively, and had caused up to 500,000 Somalis of the region, primarily of the Isaaq clan, to flee their land and cross the border to Hartasheikh in Ethiopia as refugees in what was described as "one of the fastest and largest forced movements of people recorded in Africa", which resulted in the creation of the world's then-largest refugee camp and the displacement of an additional 400,000 Somalis. The scale of destruction led to Hargeisa becoming known as the 'Dresden of Africa'. The killings happened during the Somali Civil War and have been referred to as a "forgotten genocide".
In the countryside, the persecution of Isaaq included the creation of a mechanised section of the Somali Armed Forces dubbed as Dabar Goynta Isaaqa (The Isaaq Exterminators) consisting entirely of non-Isaaqs (mainly Ogaden); this unit conducted a "systematic pattern of attacks against unarmed, civilian villages, watering points and grazing areas of northern Somalia (Somaliland), killing many of their residents and forcing survivors to flee for safety to remote areas". This resulted in entire villages being depopulated and towns getting plundered. Rape was also used as a weapon against Isaaqs.
https://en.wikipedia.org/wiki/Isaaq_genocide