from the Introduction:
Interested in Chaosium's Call of Cthulhu and Cthulhu Dark Ages? You're not alone!
Call of Cthulhu is Chaosium's classic role-playing game of Lovecraftian horror in which ordinary people are confronted by the
terrifying and alien forces of the Cthulhu Mythos.
Cthulhu Dark Ages started as a supplement for Call of Cthulhu, setting the clock of Lovecraftian horror back 1000 years, right
into the Middle Ages. Cthulhu Dark Ages as a stand-alone role-playing game was published by Chaosium Inc. in 2004.
Quick Start Cthulhu Dark Ages is a direct adaptation of Quick Start Cthulhu (Quick Start Rules for the Call Of Cthulhu Role-Playing Game) written by Ben Monroe and Sandy Petersen ... Although Cthulhu Dark Ages is fully compatible with the philosophy and the game system of Call of Cthulhu, owing to particularities of the Dark Ages, some adjustments and additions to the quick start rules have been made.
All you need to play Cthulhu Dark Ages for the first time is this booklet, some dice, plenty of imagination, and your friends.
Welcome to the Worlds of Call of Cthulhu!