"Quds Force Behind the Ceasefire"

"The Iranian Quds Force (labeled a terrorist organization by the US) was behind the Muqtada al-Sadr ceasefire which halted much of the violence in Basra, Baghdad, and much of southern Iraq. The Iranian foreign minister also called for an end to the bloodshed on March 29th when things were chaotic. The Tank has a writeup questioning what the ruling Iraqis ceded to Iran in doing this, and I'm certainly rattling my brain trying to figure it out as well. Iranian influence is responsible for the Hezbollah-style training of proxy militias in Iraq and it is also behind the most lethal roadside bombs, EFPs. However, Iran probably doesn't want to see inra-Shi'ite violence in Basrah, since it will cut off a large portion of their revenue stream."
LT Nixon Rants

It's simple really, if the Shi'a get too divided they might lose that top down control over the populace that the Shi'a enjoy. No one wants that, not Sadr, not Maliki , not the Iranians. Well and truth be told, the Sunnies don't want it either, but the lower classes rioted, and took over much of Anbar, and they are tolerating it for now...but not the Shi'a.