From the introduction:
The Angevin Campaign was designed sometime in 1989-90 as a setting for adult players which was intended to parallel an early medieval Europe, with magic. This was done at the request of at least one of my players who wanted something medieval with a European feel to hang his hat on. As a response to the player(s) requests I lifted the concept of the 1066 invasion to base the campaign on, to give it a simulacrum of reality but set it in an fictional fantasy world of my own making. This let my players feel comfortable with my fantasy game world as they had some idea of where the game was going from the point of their entry into it.
User summary:
Originally intended for use with Dungeons & Dragons, the campaign materials do not present rules or substantive system content and could be easily used with any system.