Gakosso, an ethnic Mbochi, was born in Inkouélé, located in the Gamboma District of Plateaux Region, and studied at the Sorbonne in France. He was a lecturer on journalism at the Marien Ngouabi University in Brazzaville, and in 1995 he criticized a press law passed by the National Assembly, accusing the government of "working to restrict press freedom". After the June–October 1997 civil war, he was Special Adviser for Communication, Posts, and Telecommunications to President Denis Sassou Nguesso from 1997 to 2002.