OK, I could have used the existing thread, but this way I generatw more blog entries :-)
The thing now is: how could an army able to resist a siege in Memphis against the lybian/egypt rebels and the Greek army/navy that went to assist them for about four years have lost the battle at Papremis against the rebls only?
Hoplologically speaking, there are certain possibilities, but all of them are a bit far-fetched, to say the least. First of all, I dunno how was Papremis at the time, so I'm making up most of this, also considering that the information of these events is basically close to nil. The setup is that Papremis has a fluvial, important harbor, not far from the town, which is located in "high" land, to avoid the annual flooding of the Nile. The conecction between harbor and town could be walled, but it's unlikely, as it would have served to channel the waters into the city in the annual floodings: not a brilliant idea, really... But if physical conditions about terrain are given, it could be possible.
In any way, and therefore, before the flood, the town is (must be) sieged by the rebels, who have (necessarily) taken control of the harbor as well, when the satrap's forces arrive. After some fluvial conflicts to try and re-take the harbor under loyal control, the scene is set-up for the ground battle.
The only know fact about this is that Achaemenes was killed or badly hurt by Inaros during that battle, and that the rebels won the upper hand, and managed to ask for Greek help to storm into Memphis.
Now, the fun begins: the satrap's army must have been good and strong, after all it was Lower Egypt's army, and it's remnants, without a power figure to back 'em up, managed to resist the combined force of Lybian rebels and Delian League army for four years, giving time to Artaxerxes I to send Megabyzos with a huge army (to be discussed sometime in the future) and re-take Memphis and siege the rebel and allied forces.
Therefore, it was not a tiny, bad, or poorly equiped army. It must have been abig, strong one, considering the Egyptians relationship to the Persians, and this being the second big time rebellion (the first one ca. 485 bloodily repressed) I wouldn't think Achaemenes would have taken it too lightly, but instead, in his place, I would have sent, if not most, at least a big and powerful army, to smash the rebellion, and as a showoff/display of strength and power to the populace, just in case anyone else thought they could rebel as well...
thus, we can agree in a powerful, loyal-side army, with Persian and Median forces displaced to Egypt, plus mercenaries, plus local conscripts, and a so-far successful rebel army, formed mainly by mercenaries Inaros's money could muster from the local garrisons, and cities in the western Delta (I have included greek Cyrenaic mercenaries, as they fall within this sphere of influence) and then by conscripted lybians and egyptians following their "rightful" pharaoh, plus anything Inaros could have had under his arm when living in Mareia, I've supposed so far a palace guard (he was of royal blood, after all... If Darius didn't kill him, why leave him completely unprotected?), and some secretly trained pluses... therefore, including all the recruiting he could have done after winning over Mareia, Naucratis and Sais, he couldn't have had such a big army to use at Papremis...
Therefore, how does a small army win a bigger, better prepared one?
Motivation is one way. Sound strategical and tactical work is another. Even pushing both into one, it was a tremendous feat... My take is that the mercenaries Inaros had, in my case the Cyrenian mercenaries, managed to take over a part of Achaemenes's army long enough to allow Inaros to fight him. Face to face combat may seem romantic, but it's feasible that both generals were up-front ahead of their armies and seeking each other; at least Persian kings were expected to lead their armies personally, despite the accounts we have by Greek historians, and Darius III's own behavior before Alexander II of Makedon... I can't see why Egyptian military traditions were to be different (Ramses II is always depicted at the Battle of Kadesh leading the army on his chariot...).
Once Inaros wounded/killed Achaemenes, morale on the persian side would have fallen very quickly, and the rest, as it is said, is History.
Another possibility is a massive (or at least big enough) betrayal of locally conscripted egyptians in the Persian, faced at the possibility of liberation from Persian rule... But that's not documented, and it would have weakened the Persian position for the battle of Memphis, which is unlikely, given the results...
Okay, the dilemma is served, what happened? I may start answering it later today, when I resume my writing, as I am writing exactly this part, but your thoughts and insights will be very welcome anyway...