The story is set approx 20,000 years in humanity's future and many of the spiritual traditions of our age have combined into new permutations by the time of the

The story is set approx 20,000 years in humanity's future and many of the spiritual traditions of our age have combined into new permutations by the time of the book's story. Such examples are the ZenSunni or the Orange Catholics. I take the use of the term jihad to be a choice by Frank to add texture and imply how many human cultures have cross-pollinated. The particulars of these religions are rarely addressed in any depth. Although, strangely, a small group of Jews pop up in the sixth book. They seem mostly un-changed compared to our modern-day Jews. Also, the indigenous people of Arrakis (the desert planet and focal point of the series) are loosely based on Bedouin culture, and so Frank co-opts arabic terminology and concepts as a jumping-off point for his character's culture. These same people are also descendants of the ZenSunni wanderers, who migrated to Arrakis long ago, and thus there is additional continuity there.