My thinking.
After the war, Arkat moved to Ralios. His zealots were the most powerful there and his enemies fewest. In addition, Ralios was the scene of his most traumatic experiences and after Nysalor's death, there were personal demons there that he wanted to get rid off to gain some measure of peace.
Arkat didn't rule, he brooded. Rule was exercised instead by his chief lieutenants acting in his name for their own interests. There was little opposition for simply the knowledge that Arkat still walked the earth terrified his enemies into inaction. The only constraint on their rule was not to annoy Arkat, especially when he's hunting down his demons.
We know the names of some of his lieutenants and the capabilities of others can be guessed at. For the Humakti, there was Maklamann who maintained faith with Arkat even when he abandoned Humakt. There were the Uz and the Boristi. For the Malkioni, there probably was an order of Seshnegi Knights who had mutated into becoming the gloranthan equivalent of the Templars. And lastly there was the terrible rabble of wretches who followed Arkat and had become lost and trapped in spiritual turmoil.
Each of the lieutenants and the factions had their Arkati lore which they guarded jealously. It was the source of their power and importance and to share it meant diluting it. Only Arkat knew everything and more and he didn't care about the petty bickering of his followers.
While Arkat still lived, Ralios was at peace. The factions simply divided up the land and its wealth among themselves. The sheer fear of incurring Arkat's wrath was enough to prevent even the contemplation of factional warfare. The leading Arkati in each faction was an Archon and they had all manners of Exarchs (deputy leaders), Nomarchs (Provincial leaders), Chiliarchs (Generals), Hipparchs (cavalry commanders), Hierarchs (Magical and Religious leaders) and so forth assisting them.
All was well until the last of Arkat's personal demons expired messily after a period of protracted agony. Arkat having attained the peace he wanted simply moved on. At first the Archons pretended that he was still in charge but as the Seshnegi and other enemies noted his absence and grew bolder in their imprudence, the Archons bowed to reality and appointed one of their own as their Autarch to provide direction and leadership.
The first Autarchs ruled wisely with the Archons and the Seshnegi and others were cowed back into submission. But the internal peace had been sustained by the fear of Arkat and when he was gone, it began to fray. The factions began to probe each other for their lore and in response, they took measures to occlude themselves. Long before the God Learners drove them underground, the factions became secret societies. When covert operations became overt feuding, the factions suspected that Gbaji was alive again and began ruthless purges against internal and external enemies. The results of these purges only weakened the Autarchy as a whole, prompting fresh fears of Gbaji's return and more purges.
The God Learners did not destroy the Autarchy, the factions destroyed it from within. What the God Learners did do was to provide the factions with an alibi for the Autarchy's death and engender a nostaglia for its return.
--Peter Metcalfe
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