The Sudan is a republic in northeastern Africa. It is the 10th largest country in the world and the largest in both Africa and the wider Arabic-speaking world. The capital is Khartoum and the largest city is Omdurman. It is a former British colony which gained its independance in 1956. It borders Egypt, Libya, Chad, the Democratic Republic of the Congo, the Central African Republic, Kenya, Uganda, Eritrea and Ethiopia. Sudan's main river is the Nile. It shares thousands of years of common history with Egypt since they were at times politically united in a single state.
Sudan has proved politically unstable since the 1950s. Both the First Sudanese Civil War (1955 - 1972) and the Second Sudanese Civil War (1983 - 2005) were among the longest-running and bloodiest conflicts in the 20th century. Conflicts continue in the area of Darfur and the government has been found guilty of war crimes by international organizations. Slavery is believed to have been widespread throughout the troubled history of the modern country. Sudan has at times been involved in conflicts with several of its neighbours.