The Char Bouba war (variously transliterated as Sharr Bubba, Shar Buba, etc.), also known as the Mauritanian Thirty Years' War or the Marabout War, took place between 1644-77 in the tribal areas of what is today Mauritania and Western Sahara as well as in the Senegal river valley. It was fought between the Sanhadja Berber tribes and Muslim populations in the river valley, led by Lamtuna Imam Nasr ad-Din, on one hand; and the Maqil Arab immigrant tribes, foremost of which was the Beni Hassan, as well as the traditional aristocracies of the Wolof states on the other, supported by the French. The war was led by Sidi Ibrahim Al Aroussi, son of the famous Cheikh Sidi Ahmed Al Aroussi (died in 1593, near to Smara, in Western Sahara). Al Aroussi, with his two sons Shanan Al Aroussi and Sidi Tounsi Al Aroussi, led a powerful force of the Hassani tribe, the Aroussi Army, to conquer the Berber Imarat in current Mauritania and gain access to Bilad as-Sudan ("the Land of the Blacks", in Senegal and Mali). The Sanhaja Berber tribal confederation had played a key role in the formation of the Almoravid dynasty, and as a result had experienced a period of strength and power throughout the Dynasty's existence. Following its defeat and disintegration the Sanhaja were left divided and weak. The more aggressive and warlike of the Sanhaja clans dominated the smaller and weaker groups, demanding tribute. Some of the weaker groups, having failed to preserve their independence, turned away from violence and instead devoted themselves to Islamic learning and piety. These groups became known as the Zawaya, or Maraboutic tribes. A relationship then formed between stronger warrior clans, who cared little for Islam, and the pious Zawaya. Arab nomads known as the Hassan later arrived in the south-western Saharan region in the 15th century and proceeded to dominate. A Moorish society then developed, consisting of the Hassan, the Zawaya, and the Lahma; client groups subservient to both the Hassan and the Zawaya.