I first came up with the idea of the Sword Channel Saga 40 years ago, and wrote the first hundred pages or so, then stopped for reasons I can't remember. I did manage to transfer the original files that were composed on Wang word processors (remember them?), or handwritten and then put into word processor, then exported them to WordPerfect (remember that?) and finally to Word, so I must have had some idea of continuing it some day.
Then a confluence of retiring, and getting inspiration from others writing books (my daughter's fiancé, the Montebello Writers Group), inspired me to finish the first book. Then while getting the first book ready to publish starting the second book, and then the third book while getting the second book ready. Three novels in one year when I had never written one (aside from starting the first novel way back when).
This book started with maps. I drew the world, going back 10,000 years before the action in the book, tracing the expansion of the human species from its homeland, pushing away other sentient species as humans are wont to do. Then people started settling down, founding city states, and having wars with each other, as humans are wont to do. There were 17 maps altogether. This year I traced the original maps with Corel Draw, so that I'd have vector graphic maps that could be zoomed into for a particular part of the story. A history was written to accompany the maps. So the world had been built, and it was a matter of having the characters interact with it.
In the beginning of Book 1, the characters live in a society that has been isolated from the rest of the world for 600 years, in a remote part of the world. They don't know what happened in the rest of the world during the time, and their written sources of the history were mostly limited to one book written twelve hundred years before, that was the cultural foundation of their society. The characters learn about the rest of the world, and more of the history, in the course of the three books.
Readers who get through all three books are "rewarded" with the 17 maps and the history in the Appendix in Book 3.