As I understand it, it began back in the 60’s with the Tuareg wanting independence.
In the past ten years the “Legitimate” government used funds provided by the US, supposedly to combat terrorism, in its’ fight against them and supress the homegrown independence movement. This in turn led many Tuareg in the military and government to side with the Tuareg and join their cause. Many of these officers had been trained in the US. In addition there had been a large Tuareg presence in the Libyan army who left, with their arms, when that government fell. This was the catalyst for what is happening today.
When the government brought in troops from other African nations, the Tuareg partnered up with groups affiliated with Al Queda to fight back and in time these same groups, allied with the more fundamentalist Tuareg, usurped power from the Tuareg in the Northern part of the country that fell to the Tuareg.
Thus it appears that you have one convoluted mess on your hands and are now throwing Western military might into the mix.
You have a government that is unable to defend itself from internal conflict and does not have the backing of a large percentage of the country.
An ethnic tribal independence movement with a history of doing things its’ own way that now has much better military training and weapons but the very tribal nature of the group keeps it from operating as a single unit.
A Muslim fundamentalist movement, also well armed, trained and with actual combat experience taking advantage of a fractured country and the very looseknit tribal nature of the Tuareg.
The military might of assorted African nations brough in to combat the insurrection. Again, not a single solidifying unit but a cadre of many countries, none of whom have the needed skills to conduct desert warfare in a land where the defenders have resided for centuries.
And now the former colonial master, France, Initially trying to use bombing to supress the rebel groups. Now they are sending in ground troops.
This is going to get extremely messy.
In my opinion, the French need to bring in the Tuareg. They will have to grant them their own country once the fundamentalists are crushed, but this is going to be the only way they have a chance of defeating the terrorist groups with the least amount of retaliation in Europe.
The present government will have to contend themselves with what land they now hold with the guarantee that they will not lose any more of it.