I can't think of a form of Gnosticism that had more than one Demiurge. Although the name is borrowed from a neutral creator-figure in Platonic philosophy, the Demiurge was an example of "splitting" (as children sometimes do with their parents): God in Gnosticism held the libration, the light, the goodness traditionally associated with God while the Demiurge (called Yaldabaoth or Saklas, both Aramaic names) was the taskmaster, the arrogant and petty elements of God. Gnosticism came out of Judaism, just as Christianity did (scholars argue which is the older of the two: it's difficult to date ideas). Think of Paul's discussion of the Law: what does that make God as the Lawgiver? What does that do to one's view of God?

Some branches of Judaism became disappointed with God both because of advances in science (see Gregory Riley's _River of God_ for a description of this process) and because of the general disappointment with traditional ideas of the divine (including the Greek gods) in contemporary Platonic philosophy. (Syria is also a good canditate for the origin-place of some forms of Gnosticism.)

-Kushana