I am talking about the Eastern Front coalition in Sudan. Although the article on Wikipedia is informative, I can't see when it was founded, or when the groups that make it up were founded (except for the SPLA).
When the withdrawal of the SPLA from the NDA in 2004 led to the collapse of that alliance, the BC joined with the Rashaida Free Lions and other smaller groups to form the Eastern Front rebel group. However, weak leadership, an inability to reach out to other ethnic groups in eastern Sudan, and dependence on Eritrean support led to the failure of the Eastern Front. The Eastern Sudan Peace Agreement of 14 October 2006 called for the absorption of the Eastern Front armed forces into the Sudanese military in exchange for political positions in the national government, the national assembly, and in three eastern states for the Eastern Front leadership. In making this Agreement, many members of the Eastern Front negotiating team in Asmara are reported to have not been enthusiastic at the final language, and only signed the document because they felt that they had few viable alternatives
The Beja Congress was founded in 1957 (and banned three years later), while the Free Lions were founded in 1999.