Even as we celebrate Geek Pride Day today, for fans of Sir Terry Pratchett‘s Discworld books, the May 25th is also special day. In the books, it is the anniversary of The People’s Revolution of the Glorious Twenty-Fifth of May.

Depicted in the 29th Discworld book, Night Watch, the revolution saw a people’s uprising that ended the reign of Lord Winder. On every May 25th thence, a group of the uprising’s survivors gather together to honor the casualties with lilacs and one hard-boiled egg. The fallen were John Keel, Dai Dickins, Ned Coates, Billy Wiglet, Horace Nancyball, Cecil Clapman, and Reg Shoe.

In real life though, May 25 was also adopted by Pratchett’s fans to honor Pratchett’s struggles with Alzheimer’s Disease, and to also raise awareness of the disease. Fans do so by wearing lilacs on the day, just like in the books.

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