Goodreads asked Michael McAfee:

Where did you get the idea for your most recent book?

Michael McAfee A Backed Up John was something I was playing with and evolved from a couple of old friends of mine that kidded me about my white sneakers I always wore. It eventually evolved into a long running joke.
One day, I thought, "What if a character, name unknown, at that time had white sneakers that were scientifically, or magically created to never get dirty. After that, the sneakers were just a vehicle for character to be being of immense power, but with not real knowledge of this ability. After dealing with time travel, ancient gods, heroes of legend, and anachronisms galore, it was just plan fun.

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