The Steward and the Sorcerer - The Chronicles of the Northern Earth, #1

A Druid is born into the Northern Earth, a land of warring tribes surrounding kingdoms and large cities that have fallen under political stewardship.  The Druid has an immeasurable source of power yet finds that he still needs assistance from an outside source to confront a ruthless steward whose administration bears down on the entire Northern Earth.  He encounters- through use of his magic which transports him to another reality- two individuals from 1960's England who he draws back to his time and place to confront an atrocious demon the steward has let loose on the Northern Earth.