Thusly I continue a debate without pursuing a third (Fourth? Fifth? Too lazy to count) derailment of another thread. For newcomers: previously I had said
Conversely, I tend to assume that most people don't recognize any Astartes as being different from any other Astartes- the exceptions would be senior military personnel and senior nobility- meaning the sorts of nobility who compete for the position of High Lord of Terra, not the sorts of petty nobles who inhabit Scintilla. Most planetary governors probably don't know much about the chapters of the Astartes, either.
Bear in mind that there are still only 1000 (plus or minus) Ultramarines and Imperial Fists, so honestly I'd expect their primarchs to get more face time than their chapter heraldry- and no matter how many successors the smurfs have spawned, Random Citizen A is no more likely to recognize the chapter emblem of The Forty Third Sons Of Our Spiritual Liege Guilliman than they are to recognize the heraldry of any given Black Templar crusade or the Crimson Fists.
Specific chapters should be recognizable by someone with the Forbidden Lore (Astartes) skill. Most people don't have any forbidden lore, and of all of the Forbidden Lores to take, that one has some of the least potential use in political terms- were I an aristocrat in 40k, I'd rather have dirt on the Navis Nobilite or the Ecclesiarchy or the local Lord General.
If you're running a game based out of the Empire of Ultramar, then sure, the Ultramarines are going to be well known and celebrated where'er they shall roam, but I'd expect this to be similar on any world where a chapter maintains direct governance. On the flip side of that coin, if you're running a game out of Fenris I wouldn't expect the local citizenry to recognize an Ultramarine- they'd just wonder why the Great Wolf Hero of the Wolf Stars wasn't wearing his Wolf Wolfy Wolf.
To which there was a reply:
Fair enough.
The Core says:
"Of all the thousand and more Space Marine Chapters, it is the blue-clad Ultramarines that, in the mind of the countless billions of the Emperor’s subjects, personify everything that the Adeptus Astartes stands for. [...] Across the domains of the Emperor, the Ultramarines are celebrated as heroic, virtuous, and noble defenders of Humanity, their deeds celebrated in devotional works the length and breadth of the galaxy." (page 53)
I deviate from that, as mentioned, by having them be the model Astartes for the military-inclined citizens and the Blood Angels and Space Wolves for the common man. Also, Ultras are a more local force than the Blood Angels, who operate much more heavily throughout the entire galaxy.
Alex
So while ak-73 references core fluff, rather than repeating that FFG fluff seems borked in so many ways (along with much GW fluff), I shall refrain from further neckbearding and point out that the Ultramar
Empire
Sector spans enough heavily populated systems to count as many billions. Their reach goes well beyond the sector as well, so I could see their fame spreading a good distance. However!
Rather than repeating the (in my opinion) necessarily localized nature of the reputation of any chapter (however well known, successor or not), I think the best the common man could hope for would be to admire, or even revere, the Emperor's Angels, or however they refer to these . Differentiating chapters accurately would be quite beyond them. Ultramar has an unusual, or even exceptional, advantage in this case due to how the Ultramarines (and their successors) have ruled the sector so closely. You won't see the Space Wolves holding self-indulgent parades, nor do the Dark Angels or the Black Templar have anywhere to hold self-indulgent parades were they so inclined (they aren't). The Blood Angels might except Baal is an irradiated rock of a wasteland and they're too busy painting portraits and being sophisticated (or emo). Chapters like the Imperial Fists or Crimson Fists might but only on very rare occasions- they wander just as far afield as the Blood Angels, and don't hold homecoming parties when they get back anyway.
In short, given the example chapters and traditions that we have, I can't imagine any chapter being well known across the Imperium. The common man would speak of the Emperor's Angels in the same way we might speak of angels, and they might talk about Astartes the same way we might refer to Seraphim or the other angelic orders. Only lords-general, lords-captain and sages specializing in the matter would be likely to know a great deal more.
At least, that's how I envision the fluff. This is, of course, open to debate (and it is welcome, from ak-73 or otherwise!)