16.10.2026Omnissiah

Dark Imperium reading order: books about Roboute Guilliman and the Indomitus Crusade

Cadia has fallen, the Great Rift has split the galaxy, and Roboute Guilliman has returned to lead the Indomitus Crusade. A reading route through the Dark Imperium era, from Guy Haley's trilogy to the nine novels of Dawn of Fire.

The Dark Imperium is the current era of Warhammer 40,000, beginning at the very end of the 41st millennium. Cadia fell to Abaddon, the Great Rift — the Cicatrix Maledictum — tore across the galaxy from the Eye of Terror, and the Imperium broke in two: Imperium Sanctus, still lit by the Astronomican, and Imperium Nihilus beyond the storm. At that moment Roboute Guilliman woke from ten thousand years of stasis, became Lord Commander and launched the Indomitus Crusade, bringing the Primaris Space Marines with him.

There are already dozens of books about the era, and where to start is not obvious. Below is a route through the ones in the Ordo Lectoris catalog, in the order that makes the most sense for a first read.

EXTERNAL LINKThe Dark Imperium on the timelineEvery book of the era in in-universe order

Where to start: Guy Haley's trilogy

Guy Haley wrote the novel that opened the era and its two sequels. It is the story of a returned primarch seeing what his father's Imperium has become, and of the war for Ultramar against Mortarion and the Death Guard. The trilogy is the most direct way in: the era's central events are seen through Guilliman's own eyes.

Dark ImperiumGuy Haley · ~012.M42Start here. Guilliman returns to a ravaged Ultramar, with the new Primaris Space Marines at his side and Mortarion's plague hosts at the gates.

Plague WarGuy Haley · ~012.M42Book two. The war with the Death Guard spreads across Ultramar, and a greater power intervenes in the brothers' clash, changing how Guilliman sees the galaxy and his place in it.

GodblightGuy Haley · ~012.M42The finale. The primarchs meet on the dying garden world of Iax, where Mortarion has prepared a weapon able to kill a son of the Emperor.

EXTERNAL LINKDark ImperiumThe trilogy and the short fiction around it

Dawn of Fire: nine novels of the crusade

The era's flagship series, published from 2020 to 2025. Each novel has a different author, but the story runs on: the Indomitus fleets spread out from Terra and the series moves from front to front — Chaos, orks, the Word Bearers, the knight worlds, the Eye of Terror, the necrons. In-universe most of it takes place during the crusade itself, before the main events of Haley's trilogy, so you can also start here: both lines stand on their own.

Avenging SonGuy Haley · ~001.M42Book one. As Guilliman sends his fleets out from Terra, a battle group under Van Lesk fights the Host of Slaughter in the Machorta Sound.

The Gate of BonesAndy Clark · ~001.M42Book two. The fleet makes for the shrine world of Gathalamor, and a Custodian-led scouting mission finds the army that held it has gone silent.

The WolftimeGav Thorpe · ~001.M42Book three. Orks and the Space Wolves take centre stage as a greenskin tide near Fenris threatens Fleet Primus.

Throne Of LightGuy Haley · ~001.M42Book four. Kor Phaeron and the Word Bearers stoke rebellion in the heart of Segmentum Solar and strike at the Black Ships.

The Iron KingdomNick Kyme · ~001.M42Book five. Battle group Praxis reaches the knight world of Kamidar, and reunion with the Imperium turns into war.

The Martyr's TombMarc Collins · ~001.M42Book six. The worlds of the Golden Chain lie in ruins, and the Sisters of Battle and the Black Templars defend the last one still standing against the plague cults.

Sea of SoulsChris Wraight · ~001.M42Book seven. Fleet Secundus heads for the Eye of Terror, and a battle cruiser carrying Sisters and Space Marines fights to survive.

Hand of AbaddonNick Kyme · ~001.M42Book eight. The Hand of Abaddon's scheme nears its climax as the stories of Ferren Areios and Magda Kesh converge on the Anaxian Line.

The Silent KingGuy Haley · ~001.M42Book nine. Guilliman leads the armadas south, where the necron dynasties gather under the returned Silent King.

EXTERNAL LINKDawn of FireThe series in publication order

Returned primarchs and their sons

Guilliman is not the only primarch to return in this era. These can be read at any point after the first novel of the trilogy.

The Lion: Son of the ForestMike Brooks · ~015.M42Lion El'Jonson wakes in Imperium Nihilus and gathers the Fallen knights around him. Essential if you follow the Dark Angels.

Cypher: Lord of the FallenJohn French · ~012.M42Cypher and his Fallen break out of the Imperium's most secure prison in the middle of the Imperial Palace — told by Cypher himself, not the most reliable narrator.

Knights of MacraggeNick Kyme · ~012.M42Cato Sicarius and his Ultramarines in the crusade: their ship is lost in the warp's currents, and survival means fighting what lives there.

Beyond the Rift

Imperium Nihilus is cut off from Terra, and Guilliman has made Commander Dante its regent. These books are about the half of the galaxy the Emperor's light barely reaches.

The Devastation of BaalGuy Haley · ~012.M42The prelude: Hive Fleet Leviathan descends on Baal and every successor of the IX Legion gathers to defend their primarch's world. Best read before the next book.

Darkness in the BloodGuy Haley · ~012.M42Dante as regent of Imperium Nihilus. The Chapter rebuilds after the siege of Baal while new threats grow close by.

GenefatherGuy Haley · ~012.M42Belisarius Cawl tries to unlock the pylons that might tame the Rift, and an uninvited guest arrives at his conclave: Fabius Bile.

The short route

If you just want to step into the era: Dark Imperium → Plague War → Godblight, then Avenging Son and on through Dawn of Fire to The Silent King. The Lion: Son of the Forest works well after the third or fourth Dawn of Fire book, once the shape of the broken Imperium is clear. The full list of the era's books in in-universe order is in the series below.

EXTERNAL LINKDark Imperium: ChronologyEvery book of the era, campaign books included, in in-universe order