So, on a whim I went to the Lexicanum and checked up on the size of the Imperium ... I had thought that somewhere I read the number of worlds belonging to the empire was 250,000 ... but according to the Lex it is closer to a Million. First, my thought is - no wonder so many worlds have slipped through the cracks and are not heard from for centuries - my second thought is - "wow, neverending room for more plot and story" ... which means I must have actually read 250,000 star systems? I know - compared to the size of an entire galaxy - that isn't really outrageous ... but ... wow.

Sorry, I came to 40k with DH and have never really had time to wrap my mind around that. It is a mind boggling idea.

I think it's actually bigger than that... the galaxy is something like 100,000 light years across. An Imperial Sector is a cube 200 light years on each side, each containing about 75-100 habitable worlds (and presumably hundreds of uninhabitable systems too).

On the Black Library website we once had a debate about the number of sectors you could fit into the galaxy given those proportions, and we got to something ridiculous like 300,000.

I think that's a massive overestimation, personally for a number of reasons:-

1. A good 30-40% of the galaxy is the "Eastern Fringe" (Ultima Segmentum) which although technically part of the Imperium is explicitly stated to be mostly "wilderspace" packed with unconquered alien empires, black holes etc. There is probably a much lower proportion of Imperial Sectors around here.

2. Imperial Sectors, whilst often described as "cubes" don't actually stack on top of each other as neatly as cubes. If you look in the Dark Heresy rulebook, the Calixis Sector and its neighbouring Sectors aren't parallel to each other, or even touching. So clearly, there's a lot of empty space between sectors. The archaic-style maps within the DH books show neat links between the Ixaniad and Calixis Sectors, but I bet the links aren't that clear cut. Sectors aren't stacked within the imperium like tin cans in storage, they're more like individual pieces of thrown confetti hanging in the air.

3. Sectors probably vary in size a lot, too. The Calixis Sector (as the most lovingly described sector in the Canon) is probably designed to be broadly representative of an Imperial Sector, but there are probably smaller, poorer ones (in the Ultima Segemtum, say) or bigger and richer ones (say in the Segmentum Solar.) Asking "how big is a sector?" is like saying " how big is a city?" the answer of course being - it varies!

So while you can get to 300,000 sectors by stacking them into the galaxy like sardines in a can, in my opinion it doesn't work like that. I'd hazard a guess and say that there's probably somewhere between 100,000 and 150,000 sectors in the Imperium.

This means that (100,000 x say 75 planets per sector) there are more like 7.5 million inhabited Imperial worlds in the Imperium.

I always felt that the "Imperium of a million worlds" was something of an underestimation!

As far as I know its always been the million worlds of the Imperium (but I started in 3rd ed so there might be fluff from before that) and that is still only a fraction of worlds or even Habitable worlds. This is one of the reasons the Imperial Navy is perpetually overstreached, the Imperium is just so goddamn big. The navy has to not only patrol all the inhabited systems but also many others for pirate bases or other things hiding out. Given the fact that Warp Travel isn't the most precise of traveling methods combined with the sheer massive size of even one Solar System it doesn't take much to realise why the Imperium struggles.

To quote the Battlefleet Gothic rulebook on scale in space. "First of all - space is big! Very, very big. Take your conception of a long way (ie, down to the shops when it's raining hard) and multiply it by a million, then a million again... and then by another million and your not even close to how far away away things are in space."

I always figured the Imperium was more like 10,000 sectors with an average of 100 worlds each, this was based more on feel rather than solid calculations.

My definition of world was "Somewhere with a Planetary Governor" allowing all sorts of smaller rabble to be left off the lists.

Incidentally, which do people think should be most common: Space Marines, Inquisitors or Planetary Governors?

Planetary governors; space marines and inquisitors are elite specialists in their trade - be it rooting our heresy or warfare - while PGs are a necessary part of the beurocracy. The first two should be almost myth for most people ... sure they realize there is an inquisition going on and the godlike Space Marines are featured on propoganda film sometimes, but the average person never expects to see or hear from one ... while everyone is aware of the PG on some level ... like being aware of the president even though you live on the other side of the country and will likely never meet him.

Inquisitors for the win!

Speaking in rough numbers which may have little to do with the reality of 40k, there are only 1,000,000 space marines (that whole thousand chapters of a thousand marines). Likewise, if we accept that there are a million planets or millions as LB put forth, there's somewhere around 1-7.5 million planetary governors. That puts them a bit above space marines. Finally, if we accept the Calixis sector to be a "typical" Imperial sector with ~100 habitable worlds and ~200 Inquisitors working in it's bounds, then there would be, on average, 2 inquisitors per planet, or twice the number of Inquisitors as there is planetary governors.

So, Inquisitors would have to be the most common out of those tree ;-)

Yeah, but there's some hinky stuff going on in the Calixis sector. I would not put the number of Inquisitors nearly so high. If there are really two per planet, then how and why do you need one Inquisitor flying all over a sector piecing things together and gathering extended entourages when he could simply coordinate with another Inquisitor on his planet - and so on. In Eisenhorn you really get the impression there are only about a dozen Inquisitors in his sector, making his extended organizations important. If every one of them had their own planet they shared with another member the game would get a lot less interesting for alcolytes.

You'd be 14,000xp, bolt gun armed paper boys who have a good day if they get to shoot a cat that was in their way!

Also bear in mind that there is no such thing as an average sector. Calixis is very close to the EoT so obviously there a higher Inquisitor pressence and many of those might not even be solely based in the sector but needing to travel between them (unlike much of the Imperiums organisation).

It was a wise move on behalf of the Games designers to limit the scope to one sector. You get a much better feel for the size of the Galaxy and it's much easier for a GM to have games that envolve space travel even if you just have the name and type of the surrounding planets.

I reckon the number of Inquisitors and planetary Governors is probably about the same...yes, some sectors have more Inquisitors (and I agree, the Calixis Sector being near the Eye of Terror seems a prime example, especially given the focus of the Dark Heresy Game) but logically a sector like Maccarage won't need so many.

So yeah, Marines are much rarer... In fact I reckon Inquisitors and Planetary Governors outnumber them 75-1.

This sort of makes sense: the number of FBI agents and Senators in the US almost certainly is way in excess of the number of Delta force operatives, probably in similar proportions...

Inquisitors should definitely be the most numerous. They have to be, if they have any chance of finding the heresy they are charged with combating. Think about it- if the average sector has 100 habitable worlds (plus an indeterminate number of large space stations, asteroid habitats, and Emperor-only knows how many starships with a permanent population), with an average population around 10 billion people apiece (hive worlds apparently have a far higher population, feudal and feral obviously have a much lower, but we'll go with a mean of 10bn), then even if the sector Conclave consists of 300-400 Inquisitors, each with an indeterminate number of Interrogators, Explicators and assorted other acolyte cells, then that still means that each individual inquisitor has to be on the guard for heresy in a population of over 2,500,000,000, quite exclusive of those whose job it is to watch for xenos incursions. When you consider the sheer area that said population is (or could be) spread over (potentially several light-decades, given the aforementioned plethora of starships, space stations and other oddities), it becomes obvious that even co-ordinating with other inquisitors, and making very liberal usage of acolyte cells, agents, informers and other Imperial organs, the average inquisitor should have a whelk's chance in a supernova of being able to do their job. The fact that they manage is a testament to their skill, manifest destiny and/or the hand of the God-Emperor...

Alasseo said:

In some ways that is what Accolytes are for. It's not so much the case that a planetary governor has an Inquisitor breathing down his neck. I'm sure the Imperium has other people for that (Commisars?).

On the other hand there's a lot more for an inquisitor to be worried about than the planetary governers. I think in many cases an inquisitor with an efficient network of spys and acolytes should be able to cover several planets, especially less populated worlds but then Inquisitors don't work together to work effiecently all the time. Even when they do different ordos might people covering the same area.

Funny, I was thinking about the number of Inquisitors myself the other day. I think there has to be an average of several per world; there are so many hresies in so many places at the same time, only a decent amount of resources would stop the Imperium falling apart. Even on smaller worlds there will probably be at least a half-dozen serious crimes that would necessitate Inquisitorial attention going on at any one time, and thats not including all the smaller heresies like possession of proscribed materials or contact with outlawed individuals and organisations that will also be lurking. More important planets attract more heresy and thus more Inquisitors, so whilst there may only be a handful looking over a backwater sub-sector, there will be many more in the more important places, because thats where they're needed.

Kaihlik said:

Haha, I was going to answer the OP's question with "Think of something big, double it, do this a thousand times. Then give up becauseyou're still thinking too small!" but it looks like BFG got there first.

However, the only relevant answer to this question is "Big enough for you to do pretty much what you want in your Dark Heresy game"

As for numbers of Planetary Governors vs. Space Marines vs. Inquisitors:

Space Marines: least numerous - only a million or so, and mostly only in a few places (they don't wander around on their own). And if you're seeing them, chances are you're a scum-sucking heretic who is about to die anyway. So the average Imperial citizen will never see one or be within a dozen light-years of one.

Planetary Governors: one per Imperial planet. Every Imperial citizen will know of one (unless they're so debased they don't know who rules them - e.g. feral worlders or scavvies)

Inquisitors: probably more than one per planet. Not much more though. In addition, a lot of them will be concentrated at Inquisitorial bases, or retired, or undercover, so the average Imperial citizen won't ever have seen one or know one's name. They might well know someone in an Inquisitor's extended network.

Keep in mind: inquisitors don't handle "minor heresies"... those are handled, normally, by the routine clerics of the ecclesiarchy.

Inquisitors are called in when the locals notice but can't find the root of a recurrent heresy, or when the Arbites suspect the clerics, or the clerics suspect the nobles or Arbites, or Imperial Guard.

Inquisitors normally send cells of operatives, not themselves. When the operatives fail, or note that they are on to something they can't handle, then the inqusitors themselves stand up and take notice.

It might be worth noting that on the back cover of this month's (July 09) UK White Dwarf, the Planetfall blurb says that for 1 every world lost, 10 are rediscovered...so the Imperium appears to be axpanding at an alarming rate, espcially for an Insitution supposed to be in terminal decay...

But how many of those new worlds are actually productive members? How many are merely break-even economies, or even a net drain? I know the Planetkill anthology has an example of a world cut loose because it had nothing else the Imperium found of use, in an economic sense, but I would have thought that that was something of an extreme case (and rather of an odd one- even if it had no more fossil fuels, or had been hunted barren, surely it can provide regiments for the Guard?). If there a significant number of systems (even a significant minority) which are actually a drain upon the Imperium's resources, it is quite plausible that the Imperium as a whole is in terminal decline.

Jack of Tears said:

Not to mention the innumerable statues of Astartes Heroes and Imperial Iconography being, in general, drenched in power armoured angels of the Emperors Wrath. But then again, citizens of different Hive Worlds might be lucky enough to see a propaganda pictcast of Space Marines in action, but the less technologically gifted worlds will probably have to settle for busts, statues and frescoes.

Nevertheless, if you're born on an Imperial World no matter how base or primitive you'll probably at least heard of the distant Emperor and his Angels. It's pretty intertwined with the creed after all.

Just thought it was worth mentioning for embelishment purposes.

Face Eater said:

WAY back in the beginning their was a quote which has since been refined into that little briefing at the begging of the 40k books but in the original it read...

"Millions of worlds with billions of people." and I've always assumed that to be an accurate answer. Space is called SPACE for a reason, there's a lot of it and its vast, a desert of emptiness with Oases of worlds and systems.

For my games I look at the Imperium as something unimmaginably vast, with a world where everything is legal or illegal somewhere so thiers always a world with exactly what I need for the adventure (with most of them strangely appearing in Calixis apparently).

Not only do I scale up the number of planets the Imperium holds but I also like to size up planetary populations, especially those on Hive Worlds. The sheer volume of space a hive can contain often means a few trillion people could reside on a single world... albeit in squalor relying on vast supply trains of everything from other planets to survive.

So I suggest looking at it this way, the Imperium of a million worlds are those million completely dominated worlds where the Imperium is fixed, then you've got the agri worlds and ocean planets, feral and death worlds with tiny populations that support those million core worlds and the Imperiums war machine.

- Raith

>>Keep in mind: inquisitors don't handle "minor heresies"... those are handled, normally, by the routine clerics of the ecclesiarchy.

Inquisitors are called in when the locals notice but can't find the root of a recurrent heresy, or when the Arbites suspect the clerics, or the clerics suspect the nobles or Arbites, or Imperial Guard.

Inquisitors normally send cells of operatives, not themselves. When the operatives fail, or note that they are on to something they can't handle, then the inqusitors themselves stand up and take notice.<<

Agreed, which is why I don't see there being even one Inquisitor per planet ... consider the books which feature Inquisitorial protagonists - would they be nearly so interesting if every planet had its own Inquisitor or two to oversee things? Not remotely.

And considering how much the other servants of the emperor should be able to manage on their own, it would be a complete waste of resources. I would guess about one Inquisitor per ten planets would both make sense (consideringly how rarley any single planet is going to require the intervention of an Inquisitor) and make for a more enjoyable gaming experience - making both the Inquisitors and their agents more important.

Jack of Tears said:

We've never set foot on any other planet save this one. We will live out our entire life here just as our parents did and their parents and ever human who has ever drawn breath not to mention every life form we know of. A hell of a lot of things have happened on this planet and a hell of a lot of things continue to happen. A great number of secret things I'm sure are occurring quite regularly and no one will ever be aware of everything that's happening in every corner all the time -and we live in the "information age'.

I've moved around a bit but I've never left my country of birth much less the continent (never mind the planet!) and have yet to see, hear, or otherwise be knowingly effected by people I knew 10 years ago but moved 1/4 of a continent away from and I don't think there's much of a chance of ever seeing them again unless i put forth some kind of effort. The planet's just too big... this one little planet. And our planet compared to a 40k planet (population-wise) is tinny...

When we start thinking in Space Opera terms, planets always get shrunk down. I think it's because we have no point of reference for there ever being more then one planet. We understand the concept and, based on our experiences, can guess what another planet would be like, imagine travel between them, etc, but we're still using our limited never left this planet perspective to imagine this. As such, when we think of a planet, we initially think of it as a place and when we think of a place, it's usually a much smaller thing (a city, a country or part of one for the larger sprawling countries, a geological feature, etc) that occupies a small almost minuscule part of the planet its self. We don't really automatically think of our planet as a place because, for most purposes, it isn't so much a place as it is the sum-whole of all places. Because of this, planets in space opera settings initially have a very small feel (they're a city, an island, a single geological feature, etc) and when we think of multiple planets, it's more like an island chain, different continents or countries, but rarely whole massive planets with all the divergent features and space that our one planet has. Everything found on them is usually homogeneous belonging to the planet and not a part of the planet. Granted, with a bit of work, that changes as we think more and more about said planet, but when we think of a few planets out of a thousand in a space opera setting, the shear incredible size of those planets themselves is usually lost.

In essence, I think two inquisitors could exist on a planet for several decades without ever knowing the other was there.

Edith The Hutt said:

If we assume a million worlds with one Planetary Governor to each world then there are as many Space Marines as there are Planetary Governors. It is a moot comparison, however, as any single Planetary Governor will be dealing with more than a single Space Marine at any give time, but any single Space Marines will be dealing with only the single Planetary Governor at their current location.

As for inquisitors, the organization is large enough to be feared but too small to be 100% effective - a lot of the Inquisitions work is dealing with situations "after the fact".

-K

Graver said:

An interesting and thought-provoking post - thanks. In a Dark Heresy adventure, I guess we have no choice but to boil down a planet to its essence, otherwise, onewould get lost in the background picture.

DifferenceEngine said:

Then again, when you think about it: if you're roleplaying people who are used to travelling between several planets, dont you think that their mindset would match our "place"-thought pattern a little?

I mean, for us just ravelling abroad is something a bit out of the ordinary and it takes time, money and preparation to do it. Even for business travelling people who are pretty used to it, it still takes them time to wait aboard planes and they have to pay non-ordinary sums of money for a ticket. Imagine then a person who has the same attitude towards SPACE TRAVEL, and having access to such resources probably dont find it to big a deal to travel anywhare on the planets surface. (I mean, if you are used to travel by spaceship, then getting hold of a helicporter or jet-vehicle to send you from one "country" or region to another will probably not be such a big deal).

My guess is that our way of thinking of fictional interstellar travel isn't a far stretch from how those people would think as well...