Approximately 2500 years before the rise of Darth Vader
UNSC military calendar, 2530
The Covenant 9th age of reclamation
Time and space fluctuated and bent until a single bright hole in the fabric of the universe became clearly visible. A single Covenant scout ship, christened an Unknown Truth, emerged from Slipspace above a small, striking green planet.
Clad in gold power armour the veteran Sangheili Ship master, Salleema 'Zunamee gazed through his ship's luminary to examine the world below. As the planet turned on its axis, he noticed several small groupings of familiar glyphs pocketing the planet's surface. Salleema regarded the glyphs with an intensely personal distaste.
Salleema's first mate Kalleem 'Lanuntee turned from his workstation to regard his shipmaster. His red armour shining even in the dim, purple light emitted throughout the Covenant ship.
"Humans" the younger Sangheili spat, referring to the glyphs, "does their infestation know no bounds?" he rhetorically asked.
"Easy young one" Salleema soothed, "These heretics will perish in due time. Just like the others, they will pay for their crimes."
For centuries, the Covenant luminaries had been used to detect ancient forerunner artefacts. Being based on Forerunner technology themselves, it only made sense that Forerunner technology be used to find Forerunner technology. The luminaries did so by detecting individual Forerunner glyphs discerning one piece of technology from another. But several years ago a luminary aboard a Kig-Yar scouting ship discovered a new glyph on a small world just outside Covenant space. This new glyph symbolized reclamation. Throughout the whole history of the Covenant this glyph had never found before. Such a glyph was legend.
The treasure trove of holy artefacts they hoped to recover ended up being concealed by a race of aliens which called themselves "Humanity." These aliens refused hand over their hidden Forerunner technology, provoking the Covenant to try and take the holy relics by force. Once this happened the humans started destroying the relics they possessed.
The Covenant waged war against the more primitive humans to quell their heresy and cease their destruction of the ancient technology. It was later realized that these creatures were descendants of the Forerunners who were left behind at the time of the Great Journey due to their unworthiness. The Covenant saw that their heretical beliefs was what caused them to be left behind and knew their race needed to be cleansed from the galaxy.
The worlds they were originally found on were quickly glassed from orbit. But it wasn't long after the destruction of these first few worlds that the Covenant discovered that the humans had spread to even more worlds.
In these first five years, over a hundred of their planets had been found and cleansed, a satisfying number considering how many of the insects tried to fight back against the Covenant onslaught.
So far it seemed the humans had spread themselves throughout one sector of the Galaxy, but not long ago the Hierarchs passed the order that a fleet of Covenant scout ships should spread out and search for evidence of human presences in uncommon areas of the galaxy. That was the mission of the Unknown Truth, to scout unknown territories for human occupations.
So far their scouting missions had proven unsuccessful. But it seemed the gods favoured Salleema and his crew. This planet was the first discovered outside the known territories harbouring a human infestation. This new revelation suddenly opened up new possibilities that the humans might be much more wide spread than what was first considered.
Kalleem glared at his superior "what is our course of action ship master?" he asked with a bow of his domed head.
"Contact High Charity" Salleema said casually, his mandibles clicking. He drew his gaze back to the luminary to regard the small planet once more. "The Hierarchs will want to be notified immediately of this. These heretics can't escape us, no matter where they go we will follow, we will hunt them to the ends of the universe if need be. Their heresy will not go unpunished."
The bridge roared with anticipation. Salleema raised his hand for silence and the crewmen returned to their workstations, preparing for a battle that loomed ever closer.