[AdmiralZhao]

My understanding is that a lot of the Dominions magic system was borrowed from Ars Magica, which has a similar system of combining a small selection of verbs (e.g. Conjuration) with a small selection of nouns (e.g. Death) to create spells and effects. A lot of the other concepts were carried over, like gems, searching for magical sites, magical empowerment, spell research, and item crafting & boosters. Oh, and Ars Magica also had the concept of Dominions. So there was a Fairy Dominion, a Christian Dominion, etc. where magic is weaker or stronger, and various other effects hold.

All that being said, Dominions III is the better game. Ars Magica had a lot of character and was very interesting, but I'm not sure it really works for most RPG groups.