Jaystor formed from its planetary disc eleven billion years ago. The planet once had a system of rings, but over the many millions of years, those rings fell towards the planet, seeding it not only with water for its small inland seas, but also with life.
Throughout its ancient history, Jaystor has been a very volcanic and active world, its many active volcanos and one active supervolcano causing massive devastation around the entire planet. The planet has undergone many more extinction events than Earth has at around thirty seven.
Around 9.2 billion years ago, the first known intelligent species arose on the planet. The Jaystor'e refer to them as the Jaystor'u, or the First Ones in their tongue. Evidence of the Jaystor'u were discovered when an ancient craft was discovered in eccentric orbit of Ustead by a Thulcandran-Jaystor'e joint survey of the Ustead star system. Inside the spacecraft were stone tablet written in an unknown language as well as something akin to paper and various electronic storing devices which had long since broken down and could never be recovered.
4.12 billion years later, a second intelligent species arose on the planet. The Jaystor'e refer to them as the Jaystor'tyu, or Second Ones. Evidence of their existence was discovered on one of the asteroid moons of Jaystor in the form of a small installation and remnants of a space elevator.
Around the year 180,000 BCE, the proto-Jaystor'e began to evolve near a smaller inland sea near the equator. They slowly began spreading across their ash-covered forests (thus the constant gray color of the plants). The Jaystor'e began to develop their own equivalent of agriculture and culture, creating large and formidable empires.
However around 32,000 BCE the supervolcano erupted, nearly wiping out the Jaystor'e. However a good sized portion escaped harm in an extinct volcano's lava tube underground. This group emerged and began to rebuild civilization five thousand years later. For many thousands of years after years the surviving Jaystor'e quickly multiplied and spread across the planet.
The planet was then rocked by an asteroid impact around the year 1000 CE that sent the planet into a nuclear winter. Fortunately Jaystor'e technology had advanced far enough that many of them survived for the next two thousand years in underground bunkers in order to survive the ashclouds from the collision and the eruption of the supervolcano that happened in response.
In the year 3428 a Thulcandran Expedition searching for new homes for the incoming colonists from Earth stumbled upon Jaystor. Coincidentally, the Jaystor'e had just made their first attempt at Warp and had succeeded. The Federation made first contact over a year later and the planet became a protectorate both of the Federation and the Confederacy.
In the year 18,234 CE, the planet's supervolcano showed signs that it would erupt again. However, since the Jaystor'e were now a spacefaring civilziation they had settled another less volcanic world. When it did erupt, the planet was evacuated while the Federation went in and cleaned the atmosphere in mere months. The same thing happened in 182,123 CE.
The lifeforms on Jaystor almost all have a dark brown tint to them due to the excess of ash in the air nearly constantly. So far only three intelligent native species have been known to exist on Jaystor, but many theorize that there have been other unknown species who could have existed.