In the years following their conquest, the Persians found the Ionians difficult to rule. Elsewhere in the empire, Cyrus identified elite native groups such as the priesthood of Judea – to help him rule his new subjects. No such group existed in Greek cities at this time; while there was usually an aristocracy, this was inevitably divided into feuding factions. The Persians thus settled for sponsoring a tyrant in each Ionian city, even though this drew them into the Ionians' internal conflicts. Furthermore, certain tyrants might develop an independent streak and have to be replaced. The tyrants themselves faced a difficult task; they had to deflect the worst of their fellow citizens' hatred, while staying in the favour of the Persians. In the past, Greek states had often been ruled by tyrants, but that form of government was on the decline. Past tyrants had also tended and needed to be strong and able leaders, whereas the rulers appointed by the Persians were simply place-men. Backed by Persian military might, these tyrants did not need the support of the population, and could thus rule absolutely. On the eve of the Greco-Persian wars, it is probable that the Ionian population had become discontented and was ready for rebellion.