While crosswords became popular in the early 1920s, it was not until 1942 that "The New York Times" (which initially regarded crosswords as frivolous, calling them "a primitive form of mental exercise") began running a crossword in its Sunday edition. The first puzzle ran on Sunday, February 15, 1942. The motivating impulse for the "Times" to finally run the puzzle (which took over 20 years even though its publisher, Arthur Hays Sulzberger, was a longtime crossword fan) appears to have been the bombing of Pearl Harbor; in a memo dated December 18, 1941, an editor conceded that the puzzle deserved space in the paper, considering what was happening elsewhere in the world and that readers might need something to occupy themselves during blackouts. The puzzle proved popular, and Sulzberger himself authored a "Times" puzzle before the year was out.