[3] Mesfin was born in the small village of Azien, north of Asmara, on 21 November 19, 1947.
He went to secondary school in Debre Berhan and attended the Addis Ababa University until 1966.
[2] Mesfin was a founding member of the Eritrean People's Liberation Front (EPLF) in 1973.
Before founding that organization, he had joined the Eritrean Liberation Front (ELF) in 1967 as an ordinary member.
[2] Mesfin Hagos left the ELF in 1970 with Isaias Afwerki, Major General Asmerom Gerezgiher, Solomon Weldemariam, and Tewelde Eyob.