I recently read "The Emperor's Gift" by Aaron Dembski-Bowden, and I have to say it was a pretty good read. Probably going to be doing a book review soon on it and several other books I have read recently. But it lead me to an interesting question: How large is the Space Wolves chapter. It seems to vary at times between authors, and I think too often it is taken for granted that they are about 1000 strong just because they are a Space Marine chapter.
This is much less of a straight forward question than it seems. Before you go rushing off and claiming "They are a Space Marine Chapter, which means they have 1000 Marines", let me offer a counter point that the Flesh Tearers are only about 400 strong. Yes, a lot of this has to do with battle losses, but for the sake of argument, let us agree if you can have one chapter be a little small, another can be a little large.
So to begin with, we know that the Space Wolves are a non-codex Astartes Chapter. They just don't really care about the law of the Imperium, just about the spirit of it. As such they have 12 Great Companies, or 13 if you include those lost in the eye, but we will come back to them. Each of these companies is at a different strength according to the whims of its respective Wolf Lord (Grimnar's likely being the largest). If each of these is at about 100 marines, we already have a larger than usual chapter. And each chapter has it own Wolf Guard, Long Fangs, Blood Claws, Grey Hunters, Wolf Scouts, and Vehicles. Now most chapters will share resources across companies to fit specific missions, typically borrowing from 8th, 9th and 10th companies for their respective Assault, Devastator and Scout Specialists, and sometimes taking from 6th and 7th just to boost numbers of Tactical Marines. Space Wolves don't strike me as fitting this style, each Wolf Lord being fiercely independent and unwilling to show a need for aide from another Grand Company, meaning each company needs the resources to deal with every form of battle, likely leading to larger that normal company sizes any ways.
Now let us go beyond the mere matter of organization. Let's go back all the way to the Horus Heresy. Note, there are some Prospero Burns spoilers here. Legions were all approximately 10,000 strong. However, from what I gather, Russ' legion was larger than this. Not only was it 13 Great Companies, which in themselves must have been each more massive than a chapter, but it must have been large enough that it could deal with the destruction of other Legions, which from what I gather as well he has done 3 times. Now he likely didn't suffer too bad during the destruction of the Thousand Sons at Prospero, as they had an orbital bombardment, where a larger, fiercer legion, and had allies present at the battle. In addition, even if they suffered horribly losses, they would have had time to recover somewhat before the legions were broken down into smaller chapters. And in addition to THAT, it was primarily the Ultramarines and Space Wolves that harrassed the retreating traitorous forces back to the Eye, so they must not have suffered that bad at Prospero anyways. As well, if he had destroyed legions twice before, he obviously was able to recover his numbers fast enough that by the time of the Heresy, some 200 years into the Crusade that rediscovered the Primarchs (meaning he likely destroyed/forcibly disbanded 2 legions somewhere between 250-150 years before the Heresy). So that leaves the conclusion that the SW were still legion sized at the end of the heresy, even with sending 1000+ Marines into the Eye of Terror behind the Traitor Legions. If they were significantly reduced in number, they would not have likely allowed the 13th company to follow the Legions into the eye, and even if they were allowed, it is likely the 13th Company themselves would have been weakened, and what good would a diminished company do against the vast hordes of Traitors that fled into the eye.
Now back to present day 40k. The Space Wolves have only one known second founding, the Wolf Brothers, and they were supposedly given 1/2 of the equipment and Priests of the SW, however this is likely dated info. We do know that they were not just drawn off of the space wolves, like many of the Ultramarine second foundings, and that they were a separate genetic founding. This is evidenced by the Wold Brothers demise and disbanding due to genetic instability and the curse of the Wulfen. Now if they had drawn directly from the SW and were just a new chapter, they should have been just a genetically stable, as all their numbers were Space Wolves and all the priests that administered the rituals creating new Marines were Space Wolves as well, working with directly SW geneseed. So we can conclude that was not the case and that the Wolf Brothers were a separate genetic founding (likely the 21st). And had they truly been given half the SW resources, chances are all that returned to the SW when the Wolf Brothers were disbanded.
Now why talk about the Wolf Brothers. Well my point is that since they are a separate genetic founding and not just a restructuring and that there are no other known descendants of the Space Wolves, then the Wolves must have remained legion sized, unlike the Ultramarines and all other Codex chapters. Diminished by battle loss at the end of the Heresy possibly, but larger than a chapter none the less, as they were able to send the significant resources of the 13th company into the eye. Plus they still had great recruiting stock on Fenris, which was able to maintain their numbers during the Great Crusade, so likely able to replenish their numbers over time afterwards. And for some time they had Leman Russ, who likely remained fiercely independent from Roboute and Dorn, though I can't find how long after the heresy he remained.
So it boils down to this: If the SW are only ~1000 strong, where did the rest go? And if they aren't, how large are they? And if they are still legion sized, why are they referred to as a Chapter? It is a mystery I am sure will never be answered, but feel free to voice your thoughts here and remember to hit the poll on the right!
POLL RESULTS
10000 or more 2 (12%)
5000-9999 2 (12%)
2500-4999 5 (31%)
1500-2499 6 (37%)
1000-1499 1 (6%)
Less than 1000 0 (0%)
SO It looks like we can all agree that they are at least a REALLY BIG Chapter.