Map by Anna B. Meyer
Below is the summary of the post-war regional changes.
The front line of much of the Greyhawk Wars was fought between the demigod Iuz and the stalwart forces Furyondy, Veluna (and exiled Shield Lands). Iuz smashed the kingdom in this event by fielding his best forces; summoned demons, undead hordes, and the Legion of Black Death. The Old One's alliance with Ket proved a distraction for Veluna and Bissel, yet the beygraf of Ket was double-crossed when the return of the Witch Queen Iggwilv was revealed. Aiding her son in conquest, she used her old base of power in the Yatils to marshal even more evil might and retook unaware Perrenland as well as absorbing Ket and Highfolk. The advance of Iuz through Furyondy and Veluna was halted at the Velverdyva river by the desperate valor of Dyvers and Verbobonc. A new Alliance of Good would soon emerge to give them relief.
Elsewhere, the Wolf Nomads were brought to heel by enchantment and superstition rather than by the sword. Finally, with a horde of horsemen at his disposal, Iuz stopped his empire's advance to see who might be his next opponent. Interestingly Blackmoor in this exercise goes unnoticed by all factions. Meanwhile, in the east, the Bandit Lands held their territory as they watched the empire lose the Duchy of Tenh to the Theocracy of the Pale. A late alliance with the orc city of Garel Enkdal in the Griff Mountains provided a buffer for the rise of the mighty barbarian realm of Rhizia.
The secret society revealed themselves through stealth and murder in the lands of Idee, Medegia and the Lordship of the Isles. Their efforts at a coup in Onnwal were reversed by the quick wits of the Iron League. Focusing their military might just in the east, the Scarlet Brothers pushed deeper into Aerdian lands taking Sunndi and the South Province. The naval might of the Lordship was utilized in a victorious sea war against the beleaguered Sea Barons who also was contending with the raids of Rhizia. Through intimidation and reasoning, the Brotherhood gained the alliance of Rel Astra, Menterey, and Roland who chose enlightened subjugation to barbarian razing or undead despotism.
The Brotherhood had been searching, colonizing, and recruiting the savages of the Amedio and Hepmonaland jungles for decades prior to their invasions. The onset of the Greyhawk Wars in the north had forced the Father of Obedience to move up his plans, thus the Sea Princes and much of the Jeklea Bay were never affected. An alliance with the Slave Lords and Turrosh Mak of the Pomarj did make for good timing, however. The Orcish Empire was stalled at the north Wild Coast and by the Principality of Ulek. Their pirate fleets combined with the Brotherhood's other ports, however, prove to be trouble for the besieged lands of Onnwal and Irgonate.
Desperate times make for strange alliances. The threat of Iuz and Iggwilv now at their doorstep, coupled with the second front of the Scarlet Brotherhood, the Kingdom of Keoland made a truce with all its former satellite states, including the Hold of the Sea Princes to build up their naval might and bolster the Knights of the Watch. The timely interference of adventurers made sure no Giant Troubles would plague the lands along the western mountains in this time. Farther afield, the lands of Verbobonc and Dyvers were rescued from destruction at the hand of Iuz by the arrival of good forces united from the Lortmils, Kron Hills, Lorridges, the Uleks, and even the reluctant return of the Kingdom of Celene to action.
Facing the threat of Iuz across the Nyr Dyv, the Domain of Greyhawk had to shed its neutrality and joined in a great council of Good nations at a signing in the City of Greyhawk. In this scenario Archmage Rary is a hero, using the traitorous events in his home of Ket to inspire him to advocate and mastermind an Alliance of Good along with Tenser and other wizards, clerics, and luminaries. Rary still moves his tower and base of operations to the Bright Desert. The Alliance brings the Suel ties of Keoland and the Duchy of Urnst together, along with the wisdom and arcane might of the demi-human realms combined with Dyvers and Greyhawk. The alliance also offered succor to the surrounded realms of Onnwal, Irongate and the Iron Hills, a source of highly sought-after weapon-craft. The caveat to the Alliance of Good was that another alliance of nations, fighting the same enemy, refused to join in. They are the Pact of Rel Mord.
This alliance, or as others call it the Kingdom of the Pale, was a result of Nyrond's lack of resources and exhaustion from fighting the Great Kingdom and the threat of Iuz's banditry. The Theocracy of the Pale had remained aloof in the early stages of the war, only protecting their own borders. Once Tenh was overrun and refugees poured in from there and Nyrond, they had to take action. The priesthood of Pale converted much of these refugees and turned their energy into retaking the Duchy of Tenh and securing the Artonsamay River. Northern Nyrond had long desired to be annexed by the Pale and conditions during the war led to Nyrond losing effective control of these lands, while they were more focused on defending the blighted remains of Almor.
Once the Scarlet Brotherhood took the South Province (Ahlissa) and began overtures to the southern coast of Nyrond is when the king had enough. He met with the Palish representatives and the Countess of Urnst in Rel Mord to forge a pact of defense. This had been planned in advance by the Pale it said, indeed it was the Pale stubborn and self-serving voice at the council in Greyhawk that led to the Pact's refusal to join the Alliance of Good.
Mad Overking Ivid, the Death Knights, Duke Szeffrin, Delgath, Grenell, etc. all continued to lead the once Great Kingdom into the ash heap of history. They had started with a strong campaign against their old rival of Nyrond, but soon fell into disarray as the Scarlet Brotherhood came on the scene and wiped out half the Iron League where they couldn't. To make matters worse, the Aerdians were soon raided and occupied by a vast barbarian horde from the Thillonria Peninsula. These berserk warriors had not been a major threat since the Battle of Shamblefield and the construction of Spinecastle. Now it seemed a new cause had united these tribes to not just plunder, but conquer and settle the northern ports and marches. Even the Sea Barons, at war abroad with the piratical Duxchaners, could not have anticipated the amphibious assaults on their home islands by Rhizian longships. From there, Rel Astra and the other coastal cities capitulated with the Brotherhood rather than be annihilated. The rest of Aerdy, especially the capital of Rauxes fell in on itself.
The Thillonria Peninsula is home to the barbarians of the Bitter North, but the Suel people of these lands refer to themselves as Rhizia. Through time, various tribes, snow, ice or frost had held the upper hand, but none could unite them all, it was prophesized until the Great God of the North could be freed from his ancient imprisonment. In this scenario, a band of adventurers fulfills this event by bringing the five Blades of Corusk together and summoning Vatun to Oerth. It was no trickery though. Inspired by the direction of their divine patron, the kings, and thanes of Rhizia formed an Althing, a type of democratic council of rulers and landowners, to guide their new land to war against the coming tide of Iuz, Stonefist, and their old enemy; Aerdy. The appearance of a god in the Flanaess certainly got Iuz's attention and checked his activities in the west.
Vatun would not stay long, but his divine wisdom was clear. Rhizia must fight. The gains in the south were swift and brutal, aided by Ratik who was eager to put down Bone March. Before the Great Kingdom could recall forces from the fight against Nyrond, they had lost half the North Province. Meanwhile, the rise of orcs in the Griffs and the liberation of Tenh by the Pale brought the Rhizian advance to a halt after Stonehold was overrun. Now at a pause, Rhizia is wary not of Iuz, but of the emissaries of the Scarlet Brotherhood who now seek to form an alliance of Suloise ancestry.
Another holy destiny was fulfilled in the Baklunish West, as the enigmatic Mahdi of the Desert emerged from the Dry Steppes at the fore of a massive horde of Paynim nomads and dervishes. The prophecy told this person, who would possess divine proof of his ancestry, would be the next Padishah of the Baklunish Empire. They first swept through lawless Ull, who were at first hostile to this religious figure, but then receptive when it became apparent they could make war on the civilized Baklunish lands instead.
As the Mahdi army grew to a size not seen since the Brazen Horde, the lands of Zeif levied their forces to fend off the advance. Ekbir and Tusmit however had already been in contention with the wicked return of Iggwilv and the treachery of Ket. Their high priests and monks knew the Mahdi prophecies well, so in a hallowed convention, the Mahdi met with the sultans and rulers of the west (even the Tarkhan of the Tiger Nomads) in Ekbir City. Whatever happened that day satisfied all parties as the Mahdi's claim was irrefutable and rather than civil war, all bowed to the new Padishah. For his first proclamation, the Padishah turned his gaze east. Would he now fight the Baklunish's ancient enemy the Suel or the demigod tyrant to the north?
Here is a reference to the colored regions on the below map:
Bright Red: Scarlet Brotherhood
Deep Red: Empire of Iuz
Green: Alliance of Good
Light Blue: Pact of Rel Mord
Gray: Great Kingdom
Light Purple: Rhizia
Yellow: Baklunish Empire
History of the Greyhawk Wars in full detail: