What is the setting of Jackaroo by Cynthia Voigt?
The setting is in a fictional time period, in a fictional place. However, it seems to be based loosely on medieval time periods, in a feudal system where wealthy Lords and Kings owned all of the land, and had serfs that worked the lands. This occurred all throughout Europe for centuries, up until recent times. There are many similarities between Voigt's world and the feudal system that existed in Europe. The serfs worked the land for next to no pay, they were beholden to the taxes and whims of their overlords, and most people lived in poverty. That setting is one of the situations that prompts Gwyn to make the choices that she does; she sees the injustice and wants to set it right.
Gwyn is also a woman, and it is clear that women don't hold any power or position in their society. That is why her path throughout the novel is that more interesting; she shakes off the restrictions of the setting and society, and makes her own destiny. I hope that helped a bit; good luck!