The Trolls were created by the current Great Ogre, pictured left, as slaves.
They had minds of their own, but were inhumanely treated , regularly beaten, and often denied food. They were viewed as beasts of burden.
Over time, some were discarded as too old or damaged to be useful, whilst others were left behind on hunting or food gathering trips, and forgotten about.
The Ogres considered them as tools, and otherwise irrelevant. Some survived, and in time made small villages where they tried to exist. They needed food and resources, and with the Ogres to the west, they moved east.