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40K Lore: Cadia

6 Minute Read
Dec 8 2015


Welcome to the Gateway to Hell Soldier! Grab your Las-gun and ATTEN-TION!

Cadia is a terrestrial Fortress World on the edge of the nebula known as the Eye of Terror. The planet is situated in an area of space known as the Cadian Gate, the only stable, permanent route into and out of the Eye of Terror large enough to allow the passage of battlefleets. For this reason Cadia is heavily fortified against the assaults of Chaos and has been a frequent target ofAbaddon the Despoiler‘s Black Crusades.


Physical Characteristics

Orbiting at a distance of 1.32AU from its sun, Cadia is the fourth planet of the Cadian System. It holds a breathable atmosphere conducive to human life, with an average temperature of 20 °C and surface gravity of 1.12G. The planet’s surface plays host to a variety of terrain types, from frozen tundras and wind-swept moorlands to axel-tree forests.

The Cadian Pylons

A Cadian Pylon

Perhaps the most unusual and significant feature of Cadia are the mysterious Pylons, structures of unknown origin that predate the planet’s colonization by man. Five thousand, eight hundred and ten intact Pylons are spread out across the surface of Cadia, with a further two thousand either buried or in various states of disrepair. No two are identical in design, but each one rises to precisely half a kilometer in height and extends a quarter-kilometer into the ground. Each Pylon also features slim, winding tunnels machined into them, each one no wider than a man’s head and exactly two hundred and fifty meters long.

Efforts by the Adeptus Mechanicus to study the Pylons has failed miserably, as their impenetrable surfaces are totally impenetrable to scanning by auspex and efforts to map the tunnels via Servitors have resulted in missing probes. However, it is widely believed that they are the reason for the existence of the Cadian Gate in the first place. During the 13th Black Crusade, as the warp storm Baphomael expanded to engulf the edges of the Cadian System, the Pylons simultaneously began resonating at an almost imperceptible vibration, and microscopic fractures began appearing on their surface. It was discovered that they were resonating at an amplitude similar to that produced by a Gellar Field in their effort to fight back against the encroaching storm.


Before Imperial colonization, Cadia was the home of a lost fragment of humanity that worshipped the four Gods of Chaos. This society was encountered by theWord Bearers Legion forty years before the Horus Heresy, and the prevalence of violet eyes amongst the populace was seen as a mark of mutation caused by the Eye of Terror, which also appears violet. It was on Cadia that the Word Bearers’ Primarch, Lorgar, first met Ingethel the Chosen and became inducted into the service of the Foul Powers. This civilization was eventually wiped out by Cyclonic torpedoes.


Cadia was resettled sometime in the early 32nd millennium as a direct result of the 1st Black Crusade. The early defenses of Cadia however proved to be woefully ill-prepared, its major cities indefensible as they were built in the traditional High Terra style of broad, ordered avenues. Following the 2nd Black Crusade changes with made to improve the planet’s fortifications, rebuilding the cities into their present form.

Following the Thirteenth Black Crusade, the forces of Chaos managed to establish a major foothold on Cadia, though they lost the battle in space. The result of this is that most of Cadia is now under control of Chaos forces, although they have no way currently of being reinforced.


Imperial forces keep watch on the Eye of Terror from the surface of Cadia.

As one of the most strategically important planets in the Imperium, Cadia boasts a large military presence. Battlefleet Cadia provides orbital protection for the planet and can call upon the assistance of neighboring sector fleets such as Battlefleet Agripinaa, Battlefleet Corona and Battlefleet Scarus. The planet’s surface is dotted with numerous orbital defense batteries, its skies patrolled by flights of Imperial Aircraft, and any incoming civilian craft which fails to transmit the daily access codes are liable to be shot down without question.

As a Fortress World, Cadia’s entire population belongs to some branch of the Imperial military. Perhaps most famous of all are the Cadian Shock Troopers,regiments raised for service within the Imperial Guard. The Shock Troopers are considered some of the finest soldiers in the entire Imperium, even earning the respect of the legendary Adeptus Astartes. Cadians are well-known for their discipline, marksmanship and stoic sense of self-sacrifice, and are often emulated by other regiments.

The Planetary Defense Force, known as the Cadian Interior Guard, is also counted among one of the best military organizations. This is because one out of every ten Cadians, regardless of their skills, is assigned to the Interior Guard, resulting in some of the best soldiers spending their entire military career on Cadia.


Because of its closeness to the Eye of Terror, Cadia also maintains the Internal Guard for defense against Chaos cult activities. A less well-known part of the Cadian military establishment, the Internal Guard consists of Inquisitors of the Ordo Malleus which have been permanently seconded to the Cadian military, and make frequent use of Sanctioned Psykers.


Cadian Shock Trooper Officer


Cadian society is heavily militarized, with 71.75% of its total population under arms, and a birth rate equal to the recruitment rate. Cadian children are taught how to strip, reassemble and shoot a lasgun before they are taught how to read. Prior to puberty they are sent to survive on their own on the isolated islands of the Caducades Sea during the Month of Making, and by age ten most can perform infantry field drills and are proficient in killing. All Cadians must train in the defense forces, joining the Youth Armies to train alongside regular soldiers and fight mock battles with each other in the Cadian wilderness.

Cadia is under permanent martial law, leading to a number of differences compared to other Imperial worlds. The role of Planetary Governor is a military one, known as the Governor Primus, similarly serving as leader of the Cadian High Command. In times of emergency, when the Governor Primus is incapacitated, a special military rank of Lord Castellan of Cadia exists which by common consent can take over as commander-in-chief of the Cadian military. As well, there are no Arbites on Cadia, with the role of policing the population falling upon the Cadian Interior Guard.

This martial theme extends its way into every aspect of life on Cadia. Civilian clothing incorporates camouflage patterns, available in a variety of urban and wilderness colouring, while the dwellings of both rich and poor are armoured against attack. Cities on Cadia, known as Kasrs in the local dialect, are fortresses in their own right. Each Kasr is protected by rings of massive earthworks studded with gun emplacements and weapons batteries and separated by an inner moat. Passage over the moat is controlled by hydraulic bascule bridges, each one guarded by a heavily armed barbican, and defended by the many armored fortifications and shatrovies overlooking it. Once inside, the streets of each Kasr are laid out in elaborate geometric patterns, resembling from the air like an intricate puzzle. Given the Cadian’s mastery of urban warfare, this layout allows them to hold each Kasr for months, even years, should the outer defenses fall.

The ever-constant death toll from Chaos incursions, combined with the limited amount of land available, has also lead to the implementation of the Law of Decipherability. Every graveyard on Cadia is maintained by local priests who routinely check the tombstones of the honoured dead for legibility. When a section of the cemetery is deemed illegible those graves are exhumed and the bones are added to a communal pit. Because their names are no longer known, the need to honour their memory has passed, and the space can be reused.


Cadia is heavily industrialized with a large population of skilled workers dedicated to producing military equipment. This allows Cadia to outfit its Shock Troopers with only the best military equipment. Such is the rate and scale of production on Cadia that it is the largest exporter of arms and munitions in the region.


Learn more about Cadia Here



~ So who’s the braver, the Adeptus Astartes, or the Soldiers of the Cadian Gate?


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