The setting of Warhammer 40,000 is so unbelievably vast, stretching across and grim and untamable galaxy, full of wonders and horrors. It would make a near limitless open-sandbox type of game where you would not be able to travel the length and breadth of it, even if you tried!
The Imperium of Man alone conquered over 1 million worlds during the Great Crusade. Favoring smaller terrestrial worlds, such as our homeworld, humans did not try to settle on some of the more bizarred planets in the galaxy. Since then, thousands of worlds were added and lost. The Imperium of Man would wage war to take planets, keep them for some time and some planets would be lost to the conquest of others.
The Administratum of Terra cannot even keep an accurate track of how many Space Marine Chapters there are in the Galaxy. Because of warp travel, the vastness of space and the strife across the galaxy, information is slow and inaccurate.
There are thousands of worlds inhabited by Orks, Drukhari, Craftworld Eldar, T'au and Tyranids. Dead worlds and even built-up worlds settled by the other races sometimes find themselves living on top of a Necron Tomb world as the Tombs activate and the Phaerons awaken their Legions.
We now know that the Votann inhabit the Galactic Core, worlds and astroid belts and even black holes where these advanced gene-modified humans made their homes. They are not alone in the Galactic core either with more Orks and other Xenos inhabiting that portion of space.
An unfathomable number of worlds!
Types of Worlds in the Imperium
Within the scope of just what Mankind tends to settle and hold dear are a couple dozen different worlds. There are all sorts of variants that are perhaps not so important.
The most important worlds in the Imperium for their average us are the following:
Hive Worlds
Made famous by Hives such as Necromunda and Armageddon. A Hive world is industrialized and built over with several Hives. A Hive is a massive city that covers thousands of square kilometers and is built with so many levels that the large ones dwarf Mouth Everest! One Hive alone would make a interesting and unfathomably complex are to explore with humans never leaving one or even seeing starlight!
The purpose of these worlds is sometimes a bit obscured between Industrial Worlds and Armory Worlds. The classification of being a Hive World comes with its massive population.
Usually used for one of two things: Making stuff or Creating new armies of Astra Miltarum.
While an Industrial World might look similar but have less of a population and more factories.
Forge Worlds
Not to be confused with Hive Worlds or Industrial Worlds. These are the worlds of the Adeptus Mechanicus. The Techpriests of Mars need these worlds to create the wonders of the Machine that the rest of humanity (and more of the Tech Priests themselves) see as magic.
These are the worlds that create Titans and other technological wonders.
Agri Worlds / Mining Worlds
The names speak for themselves. Basic resource worlds that are either arable or that contain all the minerals and metals humans need to feed into the Hive, Industrial and Forge Worlds need.
Environmental-centric Worlds
Jungle Worlds, Ice Worlds, Ocean Worlds, and Desert Worlds. Again the name implies that these worlds predominantly have a single biome. Sometimes they are still quite life bearing and even are settled by humans.
Dead Worlds
World with no biome and often, no atmosphere. Usually just a dead rock. Sometimes - A Necron Tomb World.
Death Worlds
These are worlds generally WITH a biome that is so inhospitable that everything from the environment to the flora and fauna are deadly and tries to kill the people that live there.
Yet humanity occupies them and sometimes these become the breeding ground for some of their most hardy and effective soldiers. The Space Wolf Chapter's Home World is Fenris the deadliest Deathworld on record. More about this frozen world later.
Catachan is a Jungle World that is classified as one fo the top 5 most deadly Death Worlds and the home world of the Catachan Jungle Fighters Regiments of the Astra Militarum. With a gravity 3x that of Earth, the humans of Catachan have evolved somewhat and are all extremely muscular.
Other Worlds
There are many other worlds. Some are dedicated to religion - Shrine Worlds and Cardinal Worlds. Some are dedicated to being market places or even resorts of a sort.
There are worlds with a variety of technological advancements. Fenris' population is all Feral. They are locked in the Viking Age and will never advance because of their struggles.
Other worlds are called Fuedal Worlds, where the humans live in the Fuedal system with Knights and Lords and such. This might bring us Astra Militarum Regiments of peasant armies from such worlds, led by knights with elite cadres of armored soldiers on horseback. Their crossbowmen are given lasguns and the Planetary Governor gets to ship them off to some warzone because of the orders he gets from Segmentum Command.
In Summary
This creates a vast scope that allows the players of Warhammer 40,000 to create any army they want. You want a specific look of your Astra Militarum? Or create a Space Marine Chapter with a specific aesthetic? You can.
Because there are over a million worlds inhabited by humanity. Only a couple hundred have been named in the course of GW writing about the lore and only a few dozen of them are defined well.
So go on! What sorts of crazy armies would YOU create?
Thank you for reading!
