Space Marines - Notable Events: Horus Heresy (ca. 005-014.M31) - The Imperium is torn apart by the Horus Heresy, the great interstellar civil war fought between the Loyalist and Traitor Space Marine Legions. The rebel Warmaster Horus, despite pledging himself and his followers to the service of Chaos is defeated in single combat aboard his flagship Vengeful Spirit  by the Emperor of Mankind at the conclusion of the Siege of Terra. Though Horus is slain, the Emperor is mortally wounded and must be placed within the arcane mechanisms of the device known as the Golden Throne. No longer able to interact directly on a day-to-day basis with Mankind, the Imperium is reorganised and reformed under the direction of the Primarch Roboute Guilliman as the Lord Commander of the Imperium and the other great lords of the Senatorum Imperialis.Great Scouring (ca. 014-021.M31) - The Loyalist Space Marine Legions, in the course of their separation and the Imperial Army succeed in driving the Traitor Legions from their remaining holdings in the galaxy, and force them to flee into the eternal Warp rift known as the Eye of Terror in the Segmentum Obscurus. The remaining nine Loyalist Space Marine Legions are subjected to the Second Founding and the organisational dictates of the Codex Astartes, resulting in the creation of approximately 1,000 individual Space Marine Chapters. The Imperial Army is divided into the separate services of the Astra Militarum (Imperial Guard) and the Imperial Navy. The newborn Astra Militarum replaces the Legiones Astartes as the primary front-line ground forces of the Imperium, with the Adeptus Astartes reserved for more specialist roles such as planetstrikes and special operations.Second Founding (021.M31) - Roboute Guilliman summons his brother primarchs to Terra. There he presents his Codex Astartes, and counsels that the Legions must be broken down into Chapters. Dorn, Vulkan and Leman Russ vehemently oppose this motion, while Corax and the Khan side with Guilliman. With tensions rising, it appears as though the Imperium has survived one civil war only to be plunged into another, However, at the eleventh hour Rogal Dorn relents, recognising that his actions are motivated by pride and anger instead of reason. With disaster averted, the Second Founding takes place, and dozens of new Space Marine Chapters are born.The Ravens' Fate (Unknown Date.M32) - A sudden degeneration afflicts the gene-seed of the Raven Guard, causing organs to fail and implants to be rejected. From this time onward, the Raven Guard are forced to rely on gene-seed stocks from Terra, a factor that slows the Chapter's recruitment rates significantly but does not curtail their willingness for battle.War of the Beast (544-546.M32) - The greatest Ork invasion the Imperium has ever known to this time threatens to bring Humanity to its knees. It is the combined forces of the Adeptus Astartes who stem the green tide, at great cost.Reunited (646.M32) - A one-hundred-standard-year period of anarchy is ended by the intervention of the Space Marines. Agnathio, Chapter Master of the Ultramarines, unites over fifty Chapters of Space Marines and arrives upon Terra. Agnathio holds a locked council with the squabbling noble "rulers" of Terra. What is said has never come to light, but when the Space Marine fleets return to their homeworlds, there once again sit twelve High Lords of Terra, and unity is restored to the Imperium.Apocrypha of Davio (Unknown Date.M33) - A great and holy document attempts to list all of the Chapters of the Second Founding. It is a worthy work, but remains incomplete.The Howling (401.M34) - The Black Templars Chapter end the Catelexis Heresy by executing the Cacodominus, an alien cyborg whose formidable psychic presence allowed it to control the populance of thirteen hundred planetary systems. Alas, the Cacodominus' death scream echoes and amplifies through the Warp, burning out the minds of a billion astropaths and distorting the signal of the Astronomican. Millions upon millions of Imperial voidships are lost in the resulting upheaval and entire sub-sectors slide into barbarism without the dictats of the Adeptus Terra to guide them.Moirae Schism (Unknown Date.M35) - The Adeptus Mechanicus is torn apart by conflict and internal division during the time of internal religious strife known as the Moirae Schism. The Adeptus Astartes are not immune to such conflicts; the Iron Hands, due to their close connection to the Mechanicus, are most severely affected. The result of the religious discord is the unexpected birth of the Sons of Medusa Chapter.Cursed 21st Founding (991.M35) -  In an attempt to "improve" the creation of Space Marines the Adeptus Mechanicus tinkers with the genetic structure of the gene-seed used in the Cursed 21st Founding. The resulting Chapters of the Adeptus Astartes suffer myriad anomalies and many become corrupted by Chaos or suffer from rampant mutation and other disorders.Armoured Assault (282.M36) - The massed armoured spearheads of the Aurora Chapter break the Ork invasion of the world of Grylos.The Abyssal Crusade (321.M37) - Saint Basillius the Elder finds thirty Space Marine Chapters wanting in faith. The guilty must choose either death or to embark upon a redemptive Crusade into the Eye of Terror. All of the Chapters choose the latter mission, known as the Abyssal Crusade, and enter the Eye as an armada with their livery obscured and honour in doubt. Few return, only to discover that Basillius was actually a pawn of Chaos seeking to weaken the defences of the Imperium.Fateweaver Denied (798.M37) - The White Consuls prevail against the daemonic legions of Kairos Fateweaver.Heavenfall Massacres (956.M37)Firestorm (Unknown Date.M38) - A Daemonic incursion overruns Innocence III. Dropping from orbit, the Salamanders' 6th Company endure terrible casualties in order to defend the planet's three remaining shrine cities and their civilian populace. With the cities safe, the vengeful Salamanders purge the Daemons from Innocence III with fire and blade.Judgement of Basillius (112.M38) - The Vorpal Swords return from the Eye of Terror, leading the survivors of the Abyssal Crusade, to cast down the Chaos-tainted Saint Basillius.Siege of Haddrake Tor (ca. M40) - The Imperial Fists besiege a Chaos stronghold on Haddrake Tor. After 1st Company Captain Kleitus is killed in a teleportation mishap, Sergeant Darnath Lysander takes up the fallen hero’s weapon, the Fist of Dorn, and swears vengeance. He smashes down the gates to the heretic fortress and leads his beleaguered brothers to victory against the odds, and is named 1st Company Captain just days later.Battle for Columnus (Unknown Date.M40) - The Forge World of Columnus is set upon by a vast Ork WAAAGH!. Aiding the Technomagi in its defence are elements of the Iron Hands and Raven Guard. The battle for Columnus is horrifically costly, largely thanks to the callous defensive strategies of the Iron Hands. Though victory is secured, rumours persist about the fate of the Raven Guard, supposedly wiped out while serving as unwitting bait in an Iron Hands trap.Gothic War Begins (139.M41) - The 12th Black Crusade of Abaddon the Despoiler, also known as the Gothic War, begins in the Segmentum Obscurus' Gothic Sector. Before it is ended, it will draw in many Chapters of the Adeptus Astartes.Jorun Retaliation (143.M41) - The Drukhari Kabal of the Crimson Libation incite the wrath of the Ultramarines, Howling Griffons and Sons of Orar. The Dark Eldar are defeated, but not before the Howling Griffons' Chaplain, Armand Titus, succumbs to xenos poison and is interred within a Dreadnought.Macharian Crusade (392-399.M41) - The Macharian Crusade was a monumental, seven-year-long Imperial Crusade fought between 392.M41 and 399.M41, led by Lord Commander Solar Macharius, the Imperium's greatest Astra Militarum commander of all time and a recognised tactical and strategic genius on a par with the primarchs themselves. This Crusade took place on the far western edge of the galaxy within the Segmentum Pacificus, reaching as far as the border of the galaxy with intergalactic space and even reaching into the unknown regions of the Halo Zone. The furthest extent of this Crusade reached just beyond the edge of the Segmentum Pacificus, where not even the blessed light of the Astronomican could penetrate the dark void. Most Imperial savants agree that Macharius was the most successful and brilliant Imperial Warmaster since the Arch-Traitor Horus. Nearly a thousand worlds were brought back into the Imperial fold in only seven standard years of fighting.Macharian Heresy (399-469.M41) - After Lord Solar Macharius' death, the territories that he conquered fall to war and strife. Seventy standard years of turmoil ensues and is ended only through the combined efforts of a hundred Space Marine Chapters, working across many far-flung sectors to restore order to the region in what is known as the Macharian Heresy.Gaudinian Snare (460.M41) - On Gaudinia Prime, a Slaaneshi Daemonic entity, known as the Sapphire King, and his minions attempt to turn the Iron Hands to Chaos by unleashing a mutagenic spell into the Space Marine ranks. Fuelled by the Iron Hands' own repressed rage, the spell wreaks absolute havoc, escalating quickly towards disaster. It is only stopped when Kardan Stronos orders his brothers to disengage inhibitor protocols and free their anger upon the foe. Rallying, the surviving Iron Hands purge their enemies with uncharacteristic zeal.Corinth Crusade (698.M41) - Marneus Calgar leads the Ultramarines, Angels of Absolution, Lamenters, Silver Skulls, Scythes of the Emperor, Marines Errant and fifty Imperial Guard regiments against WAAAGH! Skargor in the Corinth Crusade. The Orks are crushed, and their threat diminished for over thirty standard years.Damocles Gulf Crusade (742.M41) - In an Imperial Crusade to drive Tau invaders from Imperial worlds in the Damocles Gulf region of the Segmentum Ultima, the Novamarines are noted for their relentless persecution of all xenos life forms. Only their recall to serve in the First Tyrannic War prevents them from being present at the Imperial assault on the Tau Sept world of Dal'yth. This campaign is known as the Damocles Gulf Crusade.A Wedge Between Allies (744.M41) - After joining forces to defeat the Alpha Legion responsible for the Redemption Rebellion, the Knights of the Raven and the Aurora Chapter swear a bitter feud against each other, each blaming the other for their grievous losses.First Tyrannic War (745.M41) - The Ultramarines and forces of the Imperial Navy successfully end the First Tyrannic War against Hive Fleet Behemoth at the Battle of Macragge, though the effort costs the lives of the entire Ultramarines 1st Company.Blood Star Campaign (748.M41) - A massive daemonic incursion into the Scarus Sector is heralded by the star Ares turning an ominous blood red. The Relictors, Rainbow Warriors and Fire Lords eventually halt the invasion but take grievous casualties, including the loss of all three Chapter Masters. The Imperium grieves for three of its mightiest heroes.Siege of Vraks (813.M41) - The Red Scorpions and Red Hunters fight to retake the Armoury World of Vraks Prime during the terrible campaign of attrition known as the Siege of Vraks. The seventeen-year-long conflict is deemed a success as the Daemons and Chaos Space Marines are repulsed. However, Vraks is reduced to the state of a Dead World as the entire civilian population is wiped out in the fighting.Lithon Purge (833.M41) - Over a hundred billion Imperial citizens are slain or captured by Dark Eldar in the Lithon System. The Revilers spend many solar months purging the xenos from the system and swear vengeance on those that escape into the Webway.Doom of Idharae (852.M41) - The Invaders Chapter launch a direct assault on the Eldar Craftworld Idharae. Though the Space Marines suffer horrific casualties, they leave the Craftworld a ruined and desolate hulk, devoid of all life.Lazar Blockade (857.M41) - The Silver Skulls' fleet blockades the Lazar System. Offering no explanation for their presence, they prosecute a secret mission to purge Necrons from the system. They obliterate the main Necron Tomb World, but secondary bases throughout the system suddenly come to life. The Silver Skulls suffer greatly, and their forces scatter into disarray. They are eventually forced to withdraw from Lazar, but to this day no outsider has ever learned the truth of what happened there.Hellabore Assault (867.M41) - Captain Alessio Cortez and the Crimson Fists 4th Company battle the Eldar of Craftworld Iyanden on the world of Hellabore. Despite suffering grievous wounds, including a stab wound to one of his hearts, Cortez leads the final assault that routs the Eldar from Hellabore.Badab War Begins (901.M41) - Lugft Huron, Chapter Master of the Astral Claws, refuses to hand over his gene-seed tithe to the Administratum and instead announces his secession from the Imperium, declaring himself the ruling "Tyrant of Badab" in the Badab Sector of the Maelstrom Zone. Over a standard decade of bitter inter-system war follows, embroiling more than a dozen Space Marine Chapters before Badab falls and the Astral Claws escape to the Warp rift known as the Maelstrom at the conclusion of the internecine conflict named the Badab War.Assault on the World Engine (925.M41) - The Necron World Engine is revealed as the architect of the destruction seen in the Vidar Sector at this time. It is destroyed on the edge of the Doranno System, thanks chiefly to the noble and complete sacrifice of the Astral Knights Chapter.Toran VI Massacres(934.M41) - The Crimson Fists defeat the Chaos Space Marine warband of the Chaos Lord Sathash the Golden.Revenge of the Asuryani (936.M41) - Craftworld Alaitoc launches a devastating attack on the Invaders' Chapter Planet. Only three companies escape the disaster and their fortress-monastery is lost. The Invaders are thereafter a fleet-based Chapter.Battle of the Black Star (939.M41) - In the sable light of the star Antilles, the Dark Hunters strike at the Renegade Punishers' stronghold, claiming over half the Traitor Marines' lives.Timeaon Deliverance (940.M41) - The Iron Snakes are ambushed during the Timeaon Planetstrike by Tau Battlesuits and saved from certain death only when the Legion of the Damned appear and launch a devastating assault on the aliens' flanks.Defence of Orask (940-997.M41) - The Red Talons successfully hold the Fortress World of Orask at the edge of the Ghoul Stars from invasion by a splinter of Hive Fleet Pythos. In recognition of their hardfought victory, the Senatorium Ultima of Ultramar honour the Chapter with the gift of the famed relic known as the Bloody Crown of Hycani.Second War for Armageddon Begins (941.M41) - When the Ork Warlord Ghazghkull Thraka unleashes a massive Ork WAAAGH! on the strategic Hive World of Armageddon in the Segmentum Solar, many Space Marine Chapters participate in its defence during what becomes known as the Second War for Armageddon.The Folly of Heroes (955.M41) - Despite direct orders to the contrary, the Brazen Claws launch a counterstrike into the Eye of Terror itself. Their last transmissions indicate the Chapter engaging a fleet of Iron Warriors vessels, but no other trace is heard of them.The Soulmaw (956.M41) - With most of their Chapter lured away by a distress call, the Silver Skulls barely manage to resist an attack on their homeworld of Varsavia by the daemonic warband known as "the Soulmaw."Bellicas Disaster (970.M41) - The Emperor's Swords Chapter is wiped out when a Necron Tomb stirs to life in the caverns of their Chapter Planet, Bellicas.Rynn's World Disaster (989.M41) - WAAAGH! Snagrod rampages across the Loki Sector, culminating with a devastating assault on Rynn's World. The Crimson Fists Chapter is left depleted and bloodied after an Imperial expedition, including many Space Marine Chapters, retakes the planet from the Orks, but they are determined to rebuild all that was lost.Flaming Vengeance (990.M41) - The Fire Lords Chapter descends on Bellicas, exterminating the Necron menace and setting the planet aflame to avenge the destruction of the Emperor's Swords.Second Tyrannic War (992-993.M41) - The Lamenters and Scythes of the Emperor Chapters are virtually destroyed fighting against the menace of Hive Fleet Kraken.Broken But Unbowed (994.M41) - Once thought destroyed in the Eye of Terror, the Brazen Claws resurface near Cadia, battered, but still fighting their long war against the forces of Chaos.The Hive Mind Hungers (995.M41) - The tendrils of the Tyranid Hive Fleet Jormungandr begin to brush against the northeastern boundaries of the Imperium. The Death Spectres and Honoured Sons led the counterattack.The Leviathan Blunted (509.997.M41) - Elements of the Ultramarines and Mortifactors Chapters stand victoriously against a spur of Hive Fleet Leviathan on Tarsis Ultra during the Third Tyrannic War.Lament of Angels (997.M41) - The Angels Revenant Chapter is destroyed while defending its fortress-monastery on the world of Liberthra against the onslaught of the Necron Maynarkh Dynasty. The Bells of Lamentation sound throughout Segmentum Tempestus at their passing.WAAAGH! Irontoof (550.998.M41) - The Genesis Chapter, alongside its Primogenitors the Ultramarines, combat and defeat the growing might of the Ork WAAAGH! Irontoof.Third War for Armageddon (757.998.M41) - The Ork Warlord Ghazghkull Thraka returns to Armageddon at the head of a new, even greater, WAAAGH! More than twenty Space Marine Chapters, including the White Scars, Salamanders, Doom Eagles, Storm Lords and Exorcists, commit forces to the beleaguered war zone. The Ork WAAAGH! is eventually broken on Armageddon during the terrible campaign remembered as the Third War for Armageddon and Ghazghkull flees into the void, pursued by the Black Templars and Commissar Yarrick who have sworn to end the wily Ork Warlord's threat to the Imperium once and for all.War in the Gildar Rift (998.M41) - The Silver Skulls destroy a Red Corsair strike force. The surviving Renegades make planetfall on several worlds in the Gildar System, but the Silver Skulls will not be thwarted and the taint of the Renegades is cleansed in a matter of weeks.The Black Sun (672.999.M41) - The Exorcists Chapter rushes to confront the Daemonic incursions around the sun Sirie.Rebirth of the Scythes of the Emperor (970.999.M41) - The Scythes of the Emperor finally emerge from the dark shadow of Hive Fleet Kraken and announce that their Chapter will be born anew.The Maelstrom Threat (980.999.M41) - A vast Chaos Space Marine fleet under the command of Huron Blackheart emerges from the Maelstrom and besieges the Chogoris, Kaelas and Sessec Systems. Rumours report Huron's force is as large as the Space Marine Legions of old, and several Chapters are tasked with its destruction.13th Black Crusade (995.999.M41) - Many Space Marine Chapters converge on the sectors surrounding the Eye of Terror in a desperate attempt to counter the influx of vile forces led by Abaddon the Despoiler in the course of his 13th Black Crusade, the largest and most potent Chaos incursion into Imperial space since the Horus Heresy. Some say it is truly the Time of Ending, yet the Adeptus Astartes stand strong in the face of their greatest enemy. Yet, despite the best efforts of the Imperium's staunchest defenders -- including the Black Templars, Imperial Fists, Dark Angels and Space Wolves -- the Fortress World of Cadia, lynchpin of the defences surrounding the Cadian Gate, eventually falls.Guilliman Awakes (ca. 999.M41) - Strange events, the appearance of the ancient Archmagos Dominus Belisarius Cawl and a cryptic alliance with a mysterious Aeldari faction known as the Ynnari conspire to awaken the Ultramarines Primarch Roboute Guilliman from his millennia-long slumber in a stasis chamber during the Ultramar Campaign. The primarch is immediately embroiled in battle with a Chaos assault by the Black Legion as Abaddon attempts to prevent his return.Great Rift Opens (ca. 999.M41) - Reality tears itself apart from the Hadex Anomaly at the core of the Jericho Reach in the Eastern Fringe, to the furthest star system of the Segmentum Obscurus. From that hole come Warp storms with an intensity not seen since the Age of Strife, cutting off the galactic north from Terra, cutting the Imperium into two halves, the Imperium Nihilus and the Imperium Sanctus. The initial period, known as the Noctis Aeterna -- or the Blackness -- is terrible indeed. For a time, all Warp travel is impossible and the far-spread planets of the Imperium are isolated, with no travel or astropathic communication between them as the Emperor's Astronomican no longer shines through the Immaterium. Worlds in their hundreds fall before the ensuing Chaos onslaught. The pulsing Cicatrix Maledictum spreads like an impenetrable curtain, robbing entire systems of the holy light of Terra.Battle of Baal (ca. 999.M41) - The Battle of Baal, also called the Devastation of Baal, was the assault by the single largest concentration of the Tyranid Hive Fleet Leviathan ever encountered by Humanity upon Baal, the homeworld of the Blood Angels Chapter of Space Marines. The battle, fought in ca. 999.M41, was a part of the wider Third Tyrannic War and also marked a key battle of the Indomitus Crusade led by the resurrected Primarch Roboute Guilliman. Due to the temporal distortions unleashed at the time of the eruption of the Great Rift, the exact date of the battle is in question; the combat may have lasted for many standard years from the point of view of Terra but only solar weeks passed for the participants. Despite heavy losses, the Blood Angels and their Successor Chapter allies, known as the Sanguinary Brotherhood, ultimately emerged triumphant, not only because of the timely intervention of the forces of Guilliman's Indomitus Crusade but also because at the moment of the Great Rift's birth the Blood Angels' ancient enemy, the Bloodthirster Ka'Bandha, led a massive legion of Khornate Daemons against the Great Devourer on Baal Prime. While the Blood Angels, their allies and the Primaris Space Marines of the Indomitus Crusade cleansed Baal proper of the Tyranid infestation, the Daemons destroyed the largest concentration of the remaining xenos lifeforms in orbit of Baal. The Daemons left behind only a mountain of Tyranid skulls shaped like the eight-pillared symbol of Khorne that dominated Baal Prime's southern hemisphere. The reasons for this intervention by one of Khorne's greatest servants remains unknown and deeply unsettling to the Blood Angels, though it may be that Ka'bandha has determined that he, and he alone, will ultimately be the architect of the sons of Sanguinius' ruin. In the wake of the Devastation of Baal, Guilliman, in his role as the lord commander of the Imperium and Imperial Regent, named Commander Dante, the Chapter Master of the Blood Angels, as the lord regent of the Imperium Nihilus, the portion of the Imperium in the galactic north cut off from Terra and the light of the Astronomican by the Great Rift. After a period of intensive reconstruction of Baal and recovery for the Chapter, the Blood Angels moved out into the Dark Imperium, determined to bring the Emperor's light back to those similarly oppressed by xenos and the servants of the Dark Gods.Indomitus Crusade (ca. 999.M41 - Ongoing) - In a hundred war zones of the Indomitus Crusade, untested strike forces of Primaris Space Marines are unleashed into battle against the forces of the Ruinous Powers. They acquit themselves well, and by the artifice of Belisarius Cawl and the strategic genius of Roboute Guilliman they prove themselves worthy inheritors of the title Adeptus Astartes. At the Battle of Raukos twelve standard years after its start, the Indomitus Crusade reaches the end of its first phase, in which the Imperium Sanctus has been largely stabilised from the assaults of the forces of Chaos. The Imperium Nihilus remains largely cut off, still beyond the light of the Astronomican, though in the wake of the Battle of Baal, Guilliman appoints Commander Dante of the Blood Angels Chapter as the lord regent of the Imperium Nihilus, to lead its defence as he judges fit.To Shield the Shrine Worlds (Unknown Date.M42) - The Shrine Worlds of the Imperial Cult are targeted with especial malice by Daemons and the Traitor Legions, most prominent amongst them the Word Bearers. In an attempt to break the sieges that hold dozens of Shrine Worlds hostage across Segmentums Solar and Pacificus, the Black Templars launch Imperial Crusade after Crusade. In their bloody endeavours they are assisted by the Iron Hands and a score of other Space Marine Chapters, along with all the forces the Adeptus Ministorum can muster.Plague Wars (ca. 012.M41) - The Plague Wars were an attempt by the Daemonic and Heretic Astartes forces of the Chaos God Nurgle, including the Daemon Primarch Mortarion and his Death Guard Traitor Legion, to conquer the Realm of Ultramar and add it to the Plague God's growing realm in realspace. By ca. 111.M42, over a hundred standard years after the start of the Indomitus Crusade, the Imperial defenders all across Ultramar were depleted in dozens of ground campaigns, while a Plague Fleet systematically destroyed the realm's Ultramar Defence Fleet and star fortresses. Guilliman returned from the Indomitus Crusade after over a standard century of campaigning to stabilise the Imperium, and his deft and defensive manoeuvres bought time to launch what became known as the "Spear of Espandor" counterattack. The combined plague armies were eventually fought to a standstill amongst the ruins of Iax, before Mortarion escaped with his forces back to their base in the Scourge Stars under cover of a Virus Bomb attack, both because of his brother's staunch defence and because Nurgle's realm in realspace had come under assault by the forces of the Blood God Khorne. In a brief respite from the work of safeguarding the Emperor's realm after Mortarion's defeat, Guilliman ordered the rebuilding and decontamination of Ultramar, as well as the establishing of new procedures for creating further Ultramarines. It was not long before new Imperial Crusades called the Lord Commander of the Imperium away from Ultramar and back out into the dark galaxy. The Ultramarines then began the work of preparing their vengeance against the servants of the Dark Gods.