Okay, so the rp is not full on fantasy, and humans are the only option. Other fantasy races like elves for example will not be encountered in the rp. The only changes to the world is that your chars are sent back in time and are authors. 

And it is preferred to go with a society that existed in the past. Since making a new culture from scratch will be hard and depending where you land. Like an area where no one historically lived in. It will take too long to start a culture and you will lag behind everyone. It is best to start with a culture that has existed and go from there. 

Is this sufficient, or do I need to add more?