New Avatar: the arrogant Guildsman from the "Dune" miniseries. (I'd have chosen Muad'dib but I'm not
that arrogant. Plus Muad'dib had better hair, especially in the Lynch version.)
There is an excellent webpage here on the Islamic influences on Frank Herbert's original: "Khalid",
Arabic and Islamic themes in Frank Herbert's "Dune"I think Herbert's vision becomes even more "prophetic" (in Islamic scholarship) where you consider that there really
wasn't a Sasanian Empire anymore after Heraclius suckerpunched it. Certainly that was part of Heraclius's propaganda, as seen in the Alexander Neshana: Kevin van Bladel, “The Alexander legend in the Qur‘an 18:83-102″, in "The Qur’ān in Its Historical Context", Ed. Gabriel Said Reynolds, (New York: Routledge, 2007). The analogy doesn't quite hold up given that the Heracleids were later able to hold the line under Constans II, and more so under Constantine IV; but in SF analogies don't have to be perfect (and really shouldn't be).
It's also interesting that Muad'dib's religious message seemed like it was foreign to the Fremen themselves, and had built on centuries of Imperial propaganda. There's an argument to be made in history that the Arabs had been primed to accept a quasi-Christian message, so that the Byzantines could use them for a holy war on the Iranians. Things don't always work out as planned though...