While not formally formed until 250 ABY, the Imperia's lineage goes back as far as 220 ABY, around when the Revenant Armada invaded Coruscant. It's believed that at this time the precursor to the organization was founded by Rannik Nurr to combat conditions on Coruscant following the Revenant invasion at the time. At that time their primary goal was to remove the Armada from their position on Coruscant, but had little indication of who they supported to take the role up once it the Armada was uprooted. It was implied that they would accept whichever governing body settled down there, but as the future moved on, it proved that they may have had other plans.