Development for both The Lightning Thief and the Percy Jackson series as a whole, commenced when Riordan first began making stories for his son Haley, who had (at the time) recently been diagnosed with ADHD and dyslexia. His son had been studying Greek mythology in second grade and requested that his father come up with bedtime stories based on Greek myths. Riordan had been a Greek mythology teacher in middle school for many years, and was able to remember enough stories to please his son. Soon Riordan ran out of myths and his son then requested that he make new ones using the same characters from Greek myths and add new ones. Thus, Riordan created the fictional character Percy Jackson and made his own story about Greek mythology.

    In June 1994, Riordan had completed his manuscript for The Big Red Tequila and began looking for agents. During that time, he visited multiple local colleges looking for good editors until he eventually found an agent. While he left his manuscript to his agent and editor to review, Riordan took his book to a group of 6th, 7th, and 8th graders to read and give their critique. Ultimately he gained their approval, and with their help, came up with the name of the book and created the way Percy's sword worked. In June 1997, Riordan signed with Bantam Books to prepare the book for publishing. In 2004, the book was sold to Miramax Books for enough money for Riordan to quit his job to focus on writing. After it was released on 28 July 2005, it sold over 1.2 million copies. The book was released in multiple versions including hardcover, paperback and audio editions. It has been translated into multiple languages and published all over the world.