"After independence, there were large demonstrations and in the early 1960s an armed rebellion by the Anya Nya movement, consisting of former southern officers whom had mutinied, commenced in the South. Full-fledged civil war between the secessionist group and the Sudanese government, concerning the status of Southern Sudan, characterised the 1963-72 period. In 1969 a group of young officers, led by Colonel Jafaar an Nimeiri, seized power in Sudan and proclaimed the establishment of a democratic republic. Nimeiri became president and banned political parties and nationalised banks and industries. In 1971, following an announcement of a planned formation of the Sudan Socialist Union (SSU), which would absorb control of all political parties, the government arrested several leading communists. This consequently led to the coup on 19 July 1971, carried out by prominent communist leaders. For three days, Nimeiri was held captured in the presidential palace before loyal army units rescued the president and arrested the coup makers. Clashes between the coup makers and the loyalist army reached the level of an armed conflict. Following the coup attempt, the government carried out mass arrests and several executions of communists and dissident military officers. The SSU was created in January 1972, as the only legal party in Sudan. However, Nimeiri was pushed to seek peace with Southern rebels in order to stay in power. Ethiopia’s Emperor Haile Selassie took a mediating role in reaching the Addis Ababa peace agreement between the government of Sudan and Anya Nya in February 1972, which ended the territorial conflict."

Source: Uppsala Conflict Data Program (Date of retrieval: 2013-07-26) UCDP Conflict Encyclopedia, Uppsala University