Around the Year of the Vibrant Land, 316 DR, a trading camp on the edge of the Great Rift was in common use by humans and halflings from the south that wanted to do business with the dwarves. It was a lawless place, rife with thievery, prone to open conflict between rivals, and near enough to the edge that an occasional drunken reveler or wayward wagon would topple over, endangering the dwellers below. The Stout Folk wanted to corral the wild traders and did so literally, by building a circular barrier made of stone rubble around the campgrounds. Those that stayed inside the perimeter were given preferential treatment by the dwarves and those that camped outside were attacked at night and driven off. Traders quickly got the idea and dwarf-built warehouses and dwarf-garrisoned guard towers soon sprang up to handle the increase in commerce.
Squatters were initially prohibited in the compound, but Shaaryan raids increased as some nomads chose to attack here instead of the well-defended Eartheart, and an ambitious young dwarf volunteered to set up a garrison if he was granted some autonomy from Underhome. Amberu Khôltar was his name, and in the Year of the Black Wing, 341 DR, he declared the camp was now Durthkhôltar, (literally, "Fort Khôltar") and allowed costers, mercenary companies, and other organizations to establish permanent residence inside the walls while he recruited other young and restless dwarves to defend the nascent city. He was dubbed "Lord Blackbeard" by the human settlers, (for his ankle-length, glossy black facial hair), and under his firm and fair management style, the city thrived.
Durthkhôltar saw rapid growth in the first decade and soon became known as simply Khôltar. By the early 360s DR, growth had become unsustainable, mainly because of the great cost of expanding the rubble wall, moving or rebuilding guard towers, and demolishing the old wall three times over a ten-year period. This was cause for alarm at the higher levels of government in the Rift and in the Year of Molten Anvils, 366 DR, they sent representatives to meet with Amberu privately. They offered him an endowment that was enough to fund the building of bigger walls for defense and make road improvements, in exchange for some of his independence. The agreement allowed Amberu to become the first Shieldlord of the city for as long as he wanted the job and established the Garthraun and Malgart, (exclusively Dwarven in the beginning) who drafted laws for him to decree. It was understood that his eventual successor would be appointed by the Deep Realm. The human inhabitants were a bit disgruntled about this change in government, but with the influx of gold, new walls being erected, highly competent law enforcement, and a paved Dunsel Trail to Eartheart initiated, prosperity soon overrode any dissent.
Right on the heels of the governmental reorganization came the invention, in the Year of the Bitter Smile, 368 DR, of a new heavy wagon by human crafter Ulbrask Hael, (for whom Hael Way got its name) that had an immediate impact on commerce. It had strength to carry greater loads, could endure rough travel on the unfinished roads, broke down less often, and was quick and easy to repair when necessary. Many fortunes were made in a few short years and newly wealthy folk built sturdy stone houses, forges, and workshops. Eventually, the space inside the new walls became scarce and buildings grew in height because it was still very risky to construct anything outside the dwarf-defended barrier.
One human blacksmith by the name of Handrorn, (namesake of the Handrornlar gate) strongly disagreed with the defensive posture the dwarves maintained over the city and demanded Lord Blackbeard help arm and equip troops to go on the offensive against the Sharryan raiders that slashed and burned every attempt to establish a venture outside the walls. Amberu was dubious about the plan but saw it as an opportunity to get the hotheads out of the city and perhaps reduce the frequency of raids so he granted them funds and a charter to wage war on behalf of the city. Handrorn, his sympathetic followers, and recruits soon swept across the southern Shaar, slaughtering nomads with fury and abandon until the raids stopped. He effectively drove them out of the lands to the west and south of Khôltar for a time, so that only Shaarmid and sites to the north were still threatened.
With Human fortunes and status rapidly ascending, some Dwarves were muttering words of envy, resentment, and indignation. One in particular, Inbrurr Harlenstar, believed that the Humans were profiting off the backs of dwarf labor and protection and demanded the leaders of the Deep Realm completely annex Khôltar, evict the humans, and reap all the profits. Cooler heads prevailed and they dismissed Inbrurr's shortsighted demands, but he chewed on his beard for a year or so and hatched a plot he thought would achieve the same ends: he would kill the Shieldlord in a way that couldn't be traced back to him and make it look like Humans were responsible, inflame dwarven opinions, spread rumors about the replacement Shieldlord sent from the Rift, and provoke the humans into defiance and rebellion so the dwarves would be forced to crush them.
In the Year of the Thoughtful Man, 374 DR, Amberu Khôltar was assassinated by poisoned weapons wielded by rogues hired by Harlenstar through multiple intermediaries. However, the killers he sent to eliminate the assassins were expected, ambushed, and two of them were captured, eventually ending up in Garthraun custody. The Garthraun offered some visiting Human wizards payment in return for unraveling the plot, and Inbrurr Harlenstar was finally implicated. The dwarven leadership banished Harlenstar but he fled into the Underdark before having to endure the ignominy of a trial.
Onskrar Hammershield was quickly appointed the new Shieldlord, and to placate the outraged citizens he formed an advisory council made up of a dozen older Human crafters, four Dwarves, two Gnomes, and a Halfling, plus eight other members that he appointed on a seasonal basis. It was intended that no seat at the table be permanent and it was hoped that the older Humans would be wise and influential to their constituents. However, over the next two hundred years, through political maneuvering and skullduggery, the twelve Human memberships became hereditary, the nonhuman seats were eliminated, and the seasonal appointees became secretaries and envoys. Hammershield was killed in a building collapse in the Year of the Ambitious Sycophant, 424 DR, and his successor, Gonth "Merrybelt" Forgegold did nothing to counter the council's machinations. Instead, he tried to glad-hand, gift, drink, aid, and favor his way into the hearts of the council and the Khôltan people, and he succeeded admirably, becoming the most well-loved Shieldlord for the next 153 years.
During Merrybelt's tenure, in the Year of the Wyvernfall, 512 DR, a councilor named Onsruur quietly set down the governing rules and laws, called the Decrees of Onsruur, formalizing what had become common practice. Thus, the name Onsruur eventually became synonymous with the laws of Khôltar and the governing body that created them. The Onsruur grew over time to sixteen families, and then twenty, and began feeling entitled to all that Merrybelt dished out, all the while tending toward decadence. Forgegold accommodated them as much as he could until the Year of the Alabaster Mounds, 577 DR, when he suddenly resigned his position and went off adventuring with some longtime friends. The Rift Dwarves appointed Angloam Dubrin to replace him, but it soon became evident that the Shieldlord position had lost much of the influence it once had.
Shieldlord Dubrin immediately began what was to be the final expansion of the city's walls, erecting the taller, inner wall with the three gates and three main roads that connected them. The Onsruur steadily chipped away at the Shieldlord's powers and authority, setting Dubrin up for a fall that would be, (it was hoped) scandalous enough to overthrow Dwarven oversight forever. Dubrin easily saw through the thinly veiled hostility, and reported the maneuverings and his suspicions to his superiors in the Deep Realm who did little but argue about a proper course of action for nearly forty years. Meanwhile, Dubrin and the defenders of Khôltar heroically repelled two major Shaaryan raids, completed the wall, survived an Orc horde, and began building a second wall outside the new one as the city grew more and more prosperous. Dubrin himself survived many "accidents" and overt assassination attempts while the Rift leaders perpetually debated.
At last, in the Year of Orcsfall, 619 DR, the dwarves decided not to move against the Onsruur families and risk an uprising. Instead, they chose to let the Humans take control of the city, knowing that Khôltar heavily depended on exports from the Rift and, if the humans ever became a credible threat, the walls or buildings could be collapsed from beneath. With spiteful humor, Dubrin brought in battalions of armed dwarves over the course of a tenday, putting fear in the hearts of the Onsruur that they were about to be arrested or worse. Then, to everyone's surprise, the army hand-delivered a flyer to every citizen proclaiming Dubrin's retirement from the office of Shieldlord and the elimination of the office itself. That evening, Dubrin and the troops vanished into tunnels and secret passages that were known only to Dwarves, and the city was instantly free but leaderless.
Into this power vacuum stepped one Onsrurr family after another, each declaring themselves the ruler of the city only to be forcibly ousted by the next. Every family involved hired as many bodyguards as they could and clashes in private chambers soon spilled out into the streets creating havoc with no respect for the law. Bloody armed conflict between gangs of bodyguards prompted Embran Orntathtar, a senior officer in the Garthraun hierarchy, to take matters into his own hands by essentially putting the city under martial law. He led the Garthraun against the Onsruur's bodyguards, declared himself Belarkh, and put to death those that refused to acknowledge his authority. The surviving Onsruur grudgingly and cautiously took his offer to become his governing council, recreating the same political structure that had existed under the Shieldlords. With order restored, people got back to business, Humans were in control of the city, and construction on the iron-clad outer wall continued.
The Onsruur were not happy with the new status quo, but Belarkh Orntathtar survived every attempt on his life and retaliated with deadly force, so they began to plot ways to manipulate his successors. The fourth Belarkh, Hulik Strathtar, was wholly in the pocket of the Onsruur, and the council had effective control of the Iron City when he took office in the Year of the Wandering Sylph, 687 DR. Years later, the Onsruur opened up the position to city-wide election but reserved the right to nominate candidates, so every Belarkh after Strathtar was hand-picked by, trained by, and beholden to the governing council families.