Tenchi Meisatsu

Tenchi Meisatsu, known internationally as The Last Calendar, is a historical novel written by Tow Ubukata and published in 2010. The narrative centers on the life of Shibukawa Shunkai, a seventeenth-century Japanese scholar and go player who was tasked by the Tokugawa shogunate with the monumental challenge of reforming the nation's calendar system. The work emerged from Ubukata's interest in the intersection of Edo-period politics, mathematics, and astronomy, aiming to humanize the scholarly figures who navigated the rigid social hierarchies of the era.

The novel was critically acclaimed upon release, winning the 7th Japan Booksellers' Award and the Eiji Yoshikawa Prize for Literature. Its success led to a film adaptation in 2012, which further solidified the story's place in modern Japanese popular culture. Ubukata is noted for his meticulous research, and this volume is frequently cited for its ability to transform dense historical and scientific details into an accessible and compelling character-driven drama.