It's possible that this is a misnomer or a localized event that has not been widely recorded.
To help clarify, please provide more information if you have it:
* Context: Where did you encounter this term? Was it in a book, article, or other source?
* Location: Is there a specific geographic location associated with this "Revolt of Gumapos"?
* Details: Are there any other details or names associated with this event?
With more information, we might be able to identify the specific historical event you are referencing or understand the context behind this term.