 They took the place which the Senatorial order had had the privilege of holding since the time of Augustus, 250 years earlier, the command of the legions and armed provinces.Illyricum was heavily colonized by the Romans beginning in the third century BC.The Romans founded the cities of Acruvium, Cibalae, Mursa, Narona, Siscia, and established colonies at Salona, Sirmium, Epidaurum, Aequum, Iader, Rhizon, and in many other cities.