There is a connection with the conflict in Libya.
Tuaregs in the past had several confrontation with the Mali government - 1963-1964, 1990-1996, 2006, 2012 -, chiefly because their integration into the state's politics and economy is seriously lacking. They wanted a place at the table and they took up fighting for it. I'm lacking in info what results they reached but I assume if they gained anything in time they always lost it again.
Prior to 2012 northern Mali was on the road of decay, arms, drugs, and human trafficking become prominent. In 2011 the "Arab Spring" sprouted the flowers of war in Libya and Tuaregs went there to join the fray from everywhere they lived, from Mali too. Then they returned in 2012 drunk on blood and some military experience under their belt to start their rebellion - which then resulted in deposing the President in a coup by the military.