What Is the Main Conflict in the Book "The Horse & His Boy"?

"The Horse and His Boy" is the fifth book in the "Chronicles of Narnia" series by C.S. Lewis. The book focuses on the native inhabitants of the world of Narnia rather than the English children who are transported there. The central conflict revolves around two runaways, Shasta and Aravis, who are working to prevent and then fight off an attack on Archenland.

The Tisroc's son, Rabadash, wants to marry Queen Susan, but the Narnians escape to avoid this forced marriage. Rabadash then gets permission from the Tisroc to invade Archenland as a means to accessing Narnia and seizing Queen Susan. Shasta is on the run after learning that his father is not really his father and was planning to sell him into slavery. He overhears this plan to invade Archenland and goes with his friend, Aravis, to warn the unsuspecting Archenlanders. Aravis is an aristocrat who has run away to avoid a forced marriage. In the resolution to the conflict, Shasta and Aravis fight in the battle to defend and ultimately save Archenland, and they create new lives for themselves. Shasta finds out that he is a prince, and he and Aravis later marry.