The Origin & History Of The Halo Rings Explained

The titular rings from the Halo franchise are highly coveted by humanity and the alien force known as the Covenant. However, the powerful installations and their history date much further than the Human-Covenant War seen in the canon of the games and books. Likewise, the same is true for the live-action Halo series streaming exclusively on Paramount+.

Set in its own “Silver Timeline”, the Halo television show has finally reached its first Halo after two seasons detailing the Human-Covenant War such as the Fall of Reach. It’s also revealed the key artifacts pointing to the powerful rings built by those who predate both races by millennia, and the rare few who can access the technology and have been called to seek the rings out. To that end, here’s the history and origins of the Halo rings in the core canon, who created them, and what they actually do.

The Halo Rings Were Built By The Forerunners

An Ancient Race of Powerful Beings

100,000 years before the events of the Human-Covenant War, the Halo rings were constructed by the ancient beings known as the Forerunners. A highly advanced technological species, the Forerunners believed themselves to be the protectors of the galaxy, tasked with guarding all known life. This was especially true in the face of the extra-galactic parasites known as the Flood.

After 300 years fighting the Flood who began overtaking multitudes across the galaxy, the Forerunners had exhausted all of their technology and strategies in their effort to contain and wipe out the parasitic species for good. To that end, the Forerunners commissioned the construction of the Halos, ring-shaped artificial worlds capable of ending the Flood scourge once and for all. To that end, the origins of the Halos look to be the same in the Halo show as well (despite its unique timeline).

What Do The Halo Rings Actually Do?

A Worst-Case Scenario For The Flood

Essentially, the Halo rings have two functions in both timelines. First and foremost, each ring is capable of being activated by a Reclaimer, members of a race chosen to inherit the Forerunner’s galactic Mantle of Responsibility (in this case humanity). Once activated, a Halo is capable of firing a devastating energy pulse designed to wipe out all lifeforms within a maximum effective radius of 25,000 light-years. To that end, the goal is to effectively starve the Flood by taking away its food source, a weapon of last resort in the event of the parasites completely overwhelming the entire galaxy.

The second purpose of the Halos was to act as research facilities for the study and containment of various Flood samples. Also known as Installations, the Halos were largely maintained by Forerunner A.I Monitors, meant to assist Reclaimers in activating the rings in the event of a Flood outbreak. As such, it’s understandable why the devastating power of a Halo ring would be so coveted by the Covenant in their mission to usurp humanity’s chosen role as the Forerunners’ successors by wiping them out (and why humanity wants to keep the rigns out of the alien alliance’s hands).

How Many Halo Rings Are There?

Installation 04 Is One of Many

While there were originally 12 Halo rings constructed by the Forerunners, several were destroyed and rebuilt in the ancient past, leaving seven total Halo installations across the galaxy numbered 01-07. There was also Installation 00, located outside the known galaxy which could be accessed via portal technology. From Installation 00, the entire Halo Array could be activated remotely and all at once, ensuring that the entire galaxy could be purged with one single action.

The Halo Array Has Only Been Fired Once

The Flood’s First Defeat

In the core Halo canon, the entire Halo Array has only been fired one single time shortly after its construction. Having no other options to stop the growing Flood, the Halo Array was activated by the Forerunners, a devastating act that saw the advanced race sacrificing themselves for the sake of the galaxy’s future. As such, the Halo Array brought The Flood to the very brink of extinction.

That said, the Flood managed to survive as seen in the very first Halo game (Combat Evolved) when the UNSC inadvertently unleashed spore samples of the parasitic race from their containment on Installation 04, the first discovered ring in the present era. However, Halo season 2 saw the Flood making a resurgence after Miranda Keyes and her mother Catherine Halsey discovered and removed a spore sample that had been locked away in a Forerunner laboratory located on the planet Onyx.

The Forerunners’ Plans After Using The Halo Array Explained

Preserving Worlds and Reseeding Life

The only way that exterminating all sentient life saves the galaxy is if there was also a plan in place by the Forerunners to ensure life could be reborn following the Flood’s extermination. The Forerunners gathered extensive DNA samples so that life could be “reseeded” after the rings did their work, and various planets known as shieldworlds were prepared to protect them from the rings’ power. Onyx was one of these shieldworlds, its status having been teased in Halo season 2 via the Forerunner ruins as well as the laboratory that was discovered with all of its samples (including the Flood’s).