of the Sahara the muyahidin were most prone to Arabization. While the zawiya tribes retained many of their Berber characteristics, the warrior tribes tried to "Arabize" as much as possible. They constructed genealogies of the ancestors of their tribes, connecting them to members of the Maqil and Arabizing their ethnonyms. Thus the Nyarzig, for instance, became the Ouled Rizg. However, this right to call oneself "Arab" was only restricted to some tribes. These tribes, the Banu Hassan or simply Hassan, were to function as a warrior class in the next centuries. The Arabized Berber tribes controlled key oasis settlements of the Sahara and played an important role in the trans-Saharan slave trade. They already used to impose heavy taxation on any traffic through their lands, while also furnishing protection, supplies, and camels. When trans-Saharan trade intensified, they developed departure and arrival centers with slave depots and intermediary secure caravan stops. In these centers, they oversaw the traffic from sub-Saharan regions to Egypt, Tunisia, Algeria, and Morocco. Timbuktu (Mali) was a central crossroad to all four routes. Ouadane, Idjil (near Atar), Azougui, Araouane, Taoudenni, and later Tindouf were important stopping-places. At the same time, the number of slaves kept in Western Sahara itself increased drastically. The Maqil tribes, who entered the domains of the Sanhaja Berber tribe, sometimes intermarried with the Berber population; the Arabo-Berber people of the region are now known as Saharawi. An exonym sometimes used to describe the Banu Hassan tribes of present-day of the region was Moors. The Arabic dialect, Hassaniya, became the dominant mother-tongue of the Western Sahara and Mauritania. Berber vocabulary and cultural traits remain common, despite the fact that many Saharawi people today claim Arab ancestry. Colonial era (1884–1975) In the second half of the 19th century, several European powers attempted to get a foothold in Africa. France occupied Tunisia and Britain Egypt. Italy took possession of parts of Eritrea, while Germany declared Togo, Cameroon and South West Africa to be under its protection. At the invitation of Germany 14 countries attended the Berlin Conference in 1884–1885 to come to an agreement amongst them about the division of the territories. At the time of the conference, 80% of Africa was still under African control. What resulted of the conference was a new map with geometric, often arbitrary, boundaries. Western Sahara came under Spanish rule, despite attempts by the Moroccan sultan Hassan I to repel