Inō Tadataka Dies Before the Map’s Completion

Inō Tadataka died in 1818, two years after the survey sequence ended. His final years had included work in Edo, while the Izu-island party had undertaken its expedition without him. His death thus followed most field measurement but preceded the final map’s official submission.

Colleagues continued the compilation in the shogunate’s astronomical office. Route records and drawings from separate expeditions had to become a coherent map set. The completed Dai Nihon enkai yochi zenzu was submitted in 1821, three years after Inō’s death. Its timing makes the remaining team’s contribution visible.

Inō was buried at Genkūji in Edo, near his teacher Takahashi Yoshitoki’s grave. Their association connects his late-life study to the survey work, while the 1821 completion records its institutional continuation. The map commonly bears Inō’s name, but its finished form includes work done after he could no longer direct it.