Harbingers of Ideas
Ideas - beliefs - hold power in this world as more people know of them, in which requires that more people first learn of it. Generally memes are able to spread because the people spreading the idea believe it, and their belief causes events ‘in line with’ the idea to manifest, and that in turn causes everyone else to begin believing in it. The people spreading this idea may simply be thinking it is news and realize that they’re spreading a meme, or they may be fleeing a disaster wrought by ideas that had taken root in the places they come from, inadvertently spreading it. Such people are referred to as ‘harbingers’ of the idea they’re spreading.
Harbingers are generally not favorably looked upon in the places they’re spreading ideas to, even if they’re useful ideas, since the establishment in those places would have vested interest in keeping things the same. But the greater problem is when they’re spreading ideas that would conflict with the ideas of the establishment, or worse, malevolent ideas, thereby spreading disaster. In these cases the establishment would generally do what they can to crack down on these harbingers.
Harbingers are generally looked upon favorably by the people of the lands they came from, as they are seen as spreading the idea that they believe in. In the case of exporting entire faiths, this means the harbingers are missionaries, and they are often lauded by their sect. In other cases they may just be spreading ideas without any underlying faiths, in which case they may receive no recognition.