People
The History of Adremesis so far
The Dragon Lords were the first life on Adremesis, and after roughly 40 years of being alone, they each separated parts of their Souls to breathe new life into Adremesis; the Raxarians.
Raxarians are huge, towering at around 2.5m (~8.2ft) tall and a mountain of raw power, they were a force to be reckoned with. Also, their relations to the Dragon Lords meant they were naturally incredibly adept at magic as they could harness the Natural Flow themselves without the need of a conduit. Raxarians are immortal and do not die naturally. They are also genderless and do not have any means to reproduce on their own terms, so the Raxarian population never grows in number. They were intelligent creatures, but saw their servitude to their Lords and to the defence of the world as their only reason for existence. There were only seven Raxarian settlements across Adremesis: Draken Thøskø, Udødlior, Serezhi Manye, Veren Sland, Vaxen Gidvow, Liset Domen and Møke Domen. One city for each Dragon Lord. They had a simple hierarchy, a single Dragon Speaker that could communicate personally with their respective Lord at the top, with everyone else "below". There was no currency since they had no need for one. You were given what you needed. There were no restraints behind class or wealth, since there was no class or wealth. Their "laws" are based on basic moral principles (if you did something wrong, you get punished) and so with a lack of justiciar system, crime fighting was sort of done by vigilantes or the guardsmen. The Raxarians are also very serious when it comes to honour, and being stripped of any honour you had for whatever reason was seen as basically the end of the world for many Raxarians.
I really could go on (trust me, I want to) but we'd be here all day.
After the Raxarians left the grand scene of Adremesis (reasons are complicated and unimportant here, just know that there are reasons), one Raxarian created humans using his own Soul - destroying him and much of Adremesis in the wake. Note that I am seriously skimming over stuff here.
Once the humans came to be, the Ancient Era started. Raxarians would essentially no longer exist, and the remains of their culture and lives would be lost to time - with very few ever finding much evidence of them (but they are still around on Adremesis, just hiding).
The Ancient Era lasts for 2197 years. Most of that time was spent by the humans constructing their societies.
After all the Kingdoms fall (the last being Barrodor, which marked the end), the Modern Era begins which is only around for 351 years until the main story, which is being set during the 351st.
Current Species & Cultures
The humans dominate Adremesis. They live in a little bit of everywhere; the plains, the mountains, the desert, the middle of nowhere. There are settlements that are bigger than others of course, but generally everything is peaceful and calm.
The Raxarians are still around. They may have the great stage of Adremesis, but the last remains of their once great nations reside in the far eastern mountains of the Melveil Ice Plains, in a huge cave system called Nyet Yem, meaning "New Home" in their language. They choose to stay completely out of the way of the humans. If a war of some description were to occur, the Raxarians would almost certainly win despite being massively outnumbered purely because they are sooooo much naturally stronger than humans are. They have been found out before, but that did not end well and was in fact the event that caused the kingdom of Excellion to fall AND what made Melveil to be as cold as it is. Scholars and the like have found evidence of something living before them, but with so little left they know very, very little about them. They also don't know that the Raxarians are still around.
They are just silently watching. Forever watching.
Needs & Relations
I mostly covered this point in the other boxes above.
I'll just simplify;
Raxarians made humans.
Raxarians "left" Adremesis.
The Ancient Era starts.
Kingdoms existed, until they didn't.
The loss of the kingdoms allowed for smaller settlements to grow.
The Modern Era started.
I think that's everything.