Ok, I'm going to sound real ignorant here. What is the IRG?
These were the elite soldiers of Saddam's Army in Gulf War I that were captured or deserted and did not want to return to Baghdad.
Sort of Saddam's equivalent to the Waffen SS of Hitler. Made up of guys from Saddam's home region around Tikrit, they got the best equipment, training, and other amenities, that the draftees of the Regular Iraqi army did not get.