The reason most believe as you have said they shouldn't is concealed right there in the paragraphs you posted:
Yes, you are correct, there was a death, and a birth of something new - the Sons of Horus died, but "most" that became the Black Legion were originally survivors of the Sons of Horus. That is going to color people's perceptions of the Black Legion. They aren't Legion 16, but they were definitely born from it. That birth may have been started by death and followed by a cautious return, but the core was still Sons of Horus.
Soon we recruited not lone warriors or squads, but warbands and warships. Time and again, Abaddon scattered us across the Eye in divided forces, bringing word of his return to his beleaguered Legion, offering amnesty and alliance to any that wished to join with us. Most of our new loyal brethren were the survivors of the shattered Sons of Horus. They came for one reason above all: survival. A dying Legion on the edge of extinction was suddenly presented with three of the most iconic symbols of its former strength.
And the number of named characters from a certain faction doesn't indicate that the work isn't about that faction, or things like the War of Secrets wasn't a book about the Dark Angels or Tau - there are very few named characters from either group in that book, yet there are clearly numerable participants from both factions based on the text - just like above, when it says "Most... were the survivors of the shattered Sons of Horus."
So what I told you was true, from a certain point of view.
The fantastic part about the Black Legion is that your personal army is going to be composed of such a small portion of the full might of the Legion that there are numerous ways you could write the lore for it and still be within the bounds of GW's overall loose canon sandbox that no one need worry.
Thanks for your reply, it's good to read. Maybe what I said is unclear; I'm not denying numbers during 'Black Legion'. What I'm saying is that the difference is ontological - to be in the BL for any member of any old legion is to be that former identity no more. As the poster after you says for their story, the black legionnaires are former members, be it of other chapters and the original extant 18 legions (unless they are new recruits in the Eye).
For me it is about that change. To some extent, this is about personhood. When someone changes religion, they stop being the former one, they become the new one; their definition of being has changed. When one changes nationality, they lose their old citizenship, they have a new one. On the individual level the person remains the same, but they are a new identity or being that is connected to a substantial change in how they are viewed and/or view themselves.
It is also about a position-based change or identity. Those former Sons of Horus remain the same people, but their membership has changed - like irl someone isnt in the army anymore, they are in the police; or they aren't in the Maoist militia, they are in the official army that replaces it; they aren't an arian ecclesiastic, they are an Athanasian ecclesiastic. Each clear or relatively sepwrate organisations with different purposes and collective identities.
Anyway as I hope you got from my writing, I like that there are former Sons in the Legion and - more so - that ADB's novels delivered in more ways than the novel Heresy series had by their date of publication in illuminating Colchisian culture. And that was with the XVI not being central in either novel. It's really good worldbuilding.
But as a collective culture, the Black Legion is a rejection of all legions and chapters, this is inherent in taking the black and removing the heraldry of old associations (much like the Red Corsairs abject their old identities by marking over their old.insignia).
Finally, as I said, by M41/2, probably most Legionnaires are going to be later creations - either heretics bred in the Eye from the mixed Geneseed collected by apothecaries like Amaruel, or renegades from.loyalist chapters. There will be a mix of members of the original (finitely numbered) legions, but all will be limited in number - limited by the cost of the Long War, and the Legion Wars before then. Finally, the BL is meant to be huge, but given the many wars it's faced, I think it's significant to note how decimated the Sons especially were by the Legion wars - and how desecrated their Geneseed was by the other legions as a special act of vindictiveness against them. So I don't know how many Sons would realistically be left within the Legion.
That's my thinking - but I imagine many later generations of new-bred Astartes and renegades would cleave to that central Colchisian identity, although through a fractured, distant, warp- and time-tainted lens wherein what exists now is very different from what existed ten millennia before.
Anyway, i totally agree that the Legion allows all our imaginings and roleplays, which is good! I just don't understand why - given how much we know now, in such detail, about the BL's founders, principles and mixed culture - we would ever see the BL as being contiguous with or equaling the XVIth. Anyway I hope you understand my thinking on this, and that it isn't too pedantic either!
Edited by Petitioner's City, 09 February 2019 - 11:41 PM.
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