The four sub-sectors of Gregora; A2631, B3247, C1325 and D0112, were formed in 088.M35 after the 3rd Gregoran Reformation. Before that the sector was divided into three separate sub-sectors. Many of the sector's worlds have been founded after the First Gregoran Reformation in M34 but there are few extremely old worlds, trailing their history all the way to the Golden Age of Mankind and the Old Night which followed.