1978 To 1991
In 1979, Polisario broke off the cease-fire and unleashed a string of new attacks on military and government targets. Mauritania, under its new government, immediately returned to the table to meet Polisario's goals, declaring full peace, a troop retreat, relinquishing their portion of Western Sahara and recognizing the Front as the Sahrawi people's sole representative. Morocco, occupying the northern half of Western Sahara and also involved in combat against Polisario, reacted with outrage, and launched a failed 1981 coup against the CMSN. Mauritania broke off relations with Rabat in protest, although ties were later restored.
In interior policy, Haidallah sought to improve relations between White Moors and Black Moors, among other things officially decreeing the ban of slavery for the first time in the country's history, but he neither tried nor achieved a radical break with the sectarian and discriminating policies of previous regimes. An attempt to reinstate civilian rule was abandoned after the above-mentioned Moroccan-sponsored coup attempt nearly brought down the regime; foreign-backed plots also involved Persian Gulf countries and Libya, and the country several times appeared to be under military threat from Morocco.
With Haidallah's ambitious political and social reform program undone by continuing instability, regime inefficiency and a plethora of coup attempts and intrigues from within the military establishment, the CMSN chairman turned increasingly autocratic, excluding other junta officers from power, and provoking discontent by frequently reshuffling the power hierarchy to prevent threats to his position.
On December 12, 1984, Maaouya Ould Sid'Ahmed Taya deposed Haidallah and declared himself Chairman of the CMSN. Like other rulers before him, he promised a swift transfer to democracy, but then made little of these promises.
The discord between conflicting visions of Mauritanian society as either black or Arab, again rose to the surface during the intercommunal violence that broke out in April 1989 (the "1989 Events"), when a Mauritania-Senegal border dispute escalated into violence between the two communities. Tens of thousands of black Mauritanians fled or were expelled from the country, and many remain in Senegal as refugees. This is also where the black Mauritanian movement FLAM is based. Although tension has since subsided, the Arab-African racial tension remains an important feature of the political dialog today. The country continues to experience ethnic tensions between its black minority population and the dominant Mauri (Arab-Berber) populace. A significant number from both groups, however, seek a more diverse, pluralistic society.
Read more about this topic: History Of Mauritania