Maki Kaji, the Godfather of Sudoku, has died at 69

While Maki Kaji didn’t necessarily invent Sudoku, he’s credited for coining the name and popularizing the game in Japan.

Last week, Kaji passed away from bile duct cancer. He was 69.

Kaji reworked existing number puzzles to create what would become Sudoku, according to Reuters. Originally called Number Place, Sudoku is short for Suji wa Dokushin ni Kagiru, which means “numbers must remain single.” The Oxford English Dictionary says it was Kaji who introduced the word “sudoku” to the English language.

“Kaji-san came up with the name Sudoku and was loved by puzzle fans from all over the world. We are grateful from the bottom of our hearts for the patronage you have shown throughout his life,” puzzle company Nikoli, where Kaji was the chief executive until this past July when he stepped down for health reasons, stated.

Prior to Kajis’s reworkings, variations of the puzzle appeared in French newspapers during the 19th century, and modern Sudoku was created by American architect Howard Garns, whose Number Place puzzles appeared in the May 1979 issue of Dell Pencil Puzzles and Word Games.

In 1980, Kaji founded Japan’s first puzzle magazine, Nikoli, which started publishing Sudoku puzzles four years later. The puzzles became popular in Japan, but it was in the mid-2000s that the game became more popular than ever after a New Zealander who had been living in Japan pitched the puzzle to a UK newspaper, which began serialization of the puzzles in 2004. The following year, Nintendo’s Brain Age, released in 2005, helped fuel Sudoku fever by featuring the game as an exercise to keep one’s gray matter limber. Sudoku and Number Place books lined bookstore sleeves in Japan and abroad. Suddenly, Sudoku was everywhere.

“I don’t want to just be the godfather of sudoku,” Kaji said in a recent interview. “I’d like to spread the fun of puzzles until I’m known as the person who established the puzzle genre in Japan.”

That he did.