Spillway began as a human settlement in the late 2080s, founded by educated refugees fleeing the anarchy of Cleveland. There they settled on the Pymatuning Reservoir and met the region's newest inhabitants, mutants. In a rare show of solidarity, the humans and mutants collaborated with one another, the mutants sharing their survival skills, and the humans their pre-flash knowledge. The humans took leadership of the community, imparting their knowledge and wisdom onto the mutants, and forever changing them. When the Radstorm Era began to truly wreak havoc on the Humans of Lake Erie, it did not spare Spillway. With their human population diminishing, the mutants took it upon themselves to preserve and keep the wisdom that had been given to them. When the radstorms continued, and the mutants found themselves without their human counterparts, expansion began under the cover of the storms. They'd found humans, but they were far different than their former tutors. Many mutants were killed by human patrols, and Spillway retaliated with force. Skirmishes with local humans became commonplace, and Spillway's residents saw the terror imposed upon other mutants by humans. Spillway would do for other mutants as their teachers had done for them. Coming to the aid of local bands of mutants, Spillway drove out many of the human settlements of the region and began to continue the legacy of their teachers.

Spillway's scribes collected stories, knowledge, raided pre-war towns for anything they could get their hands on, and entered them into Spillway's primitive records. Several surrounding tribes submitted to Spillway with the promise of their tutelage. Spillyway's benevolent intentions of educating the surrounding tribes of the region were upheld by threats of violence and overwhelming numbers, when tribes refused, they found themselves pressured and forced to submit. When the Radstorm Era came to a close, so did Spillway's hegemony. Human settlement began again and in great numbers. Entire tribes were quickly dissolved or wiped out, and Spillway had grown complacent. Spillway saw its tribal subjects either destroyed or their populations fleeing into the settlement of Spillway proper. Mutants of the region barely staved off extinction. Desperate for allies, and fearing for their survival, Spillway looked to the growing confederacy of Southpoint State, and in 2158, joined their ranks, in hopes of one day regaining its strength.

One of the first mutant settlements south of Lake Erie was Conneaut, or, as nicknamed by its human inhabitants, Stillwater. Built upon small fishing huts and reusing abandoned pre-war villas that somehow stood amidst a nuclear disaster, Stillwater's first settlers had no chance to predict its future. A small community of Native American remnants and disgruntled citizens of the now-gone United States had made it their goal to bring about a better life for the average wastelander's life, and their compassion knew no limits. Offering aid packages, supplies, and ammunition cases became a staple for this community.

However, all would change with 2105. The Radstorm era reached its peak, and mutant attacks became a common sight to see. The Allegheny National Forest was spared thanks to its vast red maple trees, but the same couldn't be said for its western outposts. Stillwater faced its first sight of raider mutants in the late winter of 2105 when a band of caravaneers, pretending to be from their western counterpart—the Spillway—managed to infiltrate through the town's gates and pull off a hostage situation. They didn't last long, as the small town quickly got back on its feet and managed to make the few remaining attackers flee.

This defense endeavor saw little success. Stillwater became prone to mutant attacks, and with time, the population plummeted. The vilomah mothers wept at the sight of their dead children; years of generosity and peace had brought Stillwater nothing but war. By 2107, the remnants of Stillwater fled east. Tales of a new mutant settlement went rampant through the tribal mutants inhabiting the forests. A new sanctuary to live freely in, devoid of human pressure. Tribal mutants flocked to this anarchic and destroyed settlement; an era of reconstruction was to begin. But it never came. Criminals and low-lives came to co-exist with tribals, and yet, despite amassing a large number of settlers, Stillwater remains anarchic and partly destroyed. Only a few homes remain inhabited, and they remain overpopulated. Nowadays, Stillwater is used as a go-to settlement for refuge from authority. The leaders of Stillwater remain a petty band of thieves that only seek out their interests—their membership within Southpoint State was only another way for them to gain more wealth.

Human caravans avoid Stillwater to this day, a foresty anarchic community inhabited by the unwelcomes. Robbery and thievery are seen as normal, and living amidst rubble is luxury.