Ethiopia-Eritrea

A long conflict between Christian and Muslim countries, still largely unresolved.

Ethiopia is (anciently) Christian and Eritrea (neighbouring Arabia) is Muslim. Eritrea (the ancient land of Aksum) had been ruled by Italy 1890-1941, then to be taken over by Britain in WW2. Eritrea was federated with Ethiopia by UN mandate in 1951. Ten years of resistance in Eritrea led American-backed Ethiopia (under Haile Selassie) to annex it, to gain sea access.
 
A 31-year civil war followed until 1991 when, after a UN-sponsored referendum in Eritrea voted for independence. Independence followed in 1993 (Ethiopia had been debilitated in the 1980s by famine and a Marxist dictatorship). Relative peace followed, but a further war broke out 1998-2000 (100,000 deaths), mainly over the border area of Badme, and political and economic policy differences.
 
Intransigence on both sides, including following international peace talks and adjudications. Severe drought and human rights abuses happen on both sides. The conflict is largely dormant but unresolved.
 

Links:

Global Issues: Ethiopia-Eritrea
Wikipedia: Eritrean-Ethiopian War