Quick – what’s a seven-letter word for “Ancient Roman city whose word squares inspired the crossword puzzle” – the last two letters are ii. The answer: “Pompeii.” From the Pompeiian Sator Square puzzle (whatever its original intention, the best linguists and scholars of our time have come up with all sorts of competing interpretations), the modern puzzle was first published in an Italian magazine, as an exercise “Per passare il tempo” – to pass the time. The fundamentals were there, but bringing the puzzles into their current form took twenty more years.

On this day, December 21, in 1913 Arthur Wynne published in the New York Globe his “word-cross,” the first modern crossword puzzle, with many of the rules still in use.

Wynne’s mental exercise did not catch on right away – other major regional papers waited years to come out with their own. The Boston Globe did not publish theirs until four years later. The New York Times, the paper that has become synonymous with quality crosswords, ironically was one of the last holdouts, first running a crossword in 1924. But as the puzzles caught on worldwide, they also mutated into word jumbles, cryptic puzzles, acrostics, and other variations that Wynne could only have dreamed about.