The Grindle-Morian Civil War is an event mentioned in The Shadow Prince. It is briefly spoken of after Link, Princess Zelda, and Charles of Moria are ambushed by a Darknut in the woods. Deciding to use his sword as means of fighting the Darknut, Charles tells Zelda to relax, mentioning that his great granfather used that sword during the Grindle-Morian Civil War.
Given the fact that it is later discovered that Charles is actually Ganon in disguise, it is possible that the Grindle-Morian Civil War never happened. This can be assumed due to Princess Zelda saying earlier in the book that she had never heard of the land of Moria, and was probably made up by Ganon to effectively cover up his disguise as Charles.
- "Charles pulls out a long, silver sword. 'Relax!' he cries to Zelda. 'My great grandfather used this sword during the Grindle-Morian Civil War!'" (The Shadow Prince (Mammoth) pg. 11)
- ""Moria? [...] I've never heard of it."" (The Shadow Prince (Mammoth) pg. 37)