- 1941: "We ought to proceed with the puzzle, especially in view of the fact that it is possible that there will now be bleak blackout hours -- or if not that, then certainly a need for relaxation of some kind....We ought not to try to do anything essentially different from what is now being done -- except to do it better." ~Lester Markel, NYT ed. (< 2 weeks after Pearl Harbor)
- Crosswords were banned in Paris during the Second World War, for fear of being misused. In fact, some editors were pulled up by the authorities when there happened weird coincidences such as these. Two days prior before an escape from the Wormwood Scrubs prison by a famous spy, a crossword had included the name of the road outside the prison.
- 1942: NYT begins publishing Sunday crosswords (2/15/1942); [.puz]; daily in 1950;
Sunday NYT later becomes popular stereotype of 'most difficult' puzzle (even though NYT Fri & Sat are harder) 
"The Herald Tribune runs the best puzzle page in existence so far, but they have gotten into a bit of a rut. Their big puzzle never ventures even one imaginative definition, and lacks the quality that I believe can be achieved and maintained. We could, I dare to predict, get the edge on them. I don’t think I have to sell you on the increased demand for this kind of pastime in an increasingly worried world. You can’t think of your troubles while solving a crossword."
~Margaret Petherbridge Farrar (Simon&Schuster crossword editor -- soon, 1st NYT crossword editor)
1942-1968: Margaret Farrar: 1st NYT crossword editor; "1st Lady of Crosswords"- "Under Margaret Farrar’s direction, the crossword 'constructors' (freelance puzzle makers) developed a clever and elaborate style. Instead of giving clues like 'Stinging insect' (BEE) and 'Bird’s home' (NEST), they phrased them as 'Nectar inspector' and 'Nutcracker’s suite. The Times' clever, whimsical style almost single-handedly ushered in a crossword renaissance, as newspapers all over the U.S. followed its lead." ~BUJBR
"Egotism, n: Doing the New York Times crossword puzzle with a pen." ~Anonymous, ?
(incorrectly attributed to Ambrose Bierce -- who died ~1914, also before "crossword" coined in ~1930)- "Men in their forties are like the New York Times Sunday crossword puzzle: tricky, complicated, and you're never really sure you got the right answer." ~Carrie Bradshaw in Sex in the City
1944: D-Day Leak?; puzzles in The Daily Telegraph contained Utah, Omaha, Overlord...- 1945: Brief Encounter (movie); Fred suggests retiring to the library by the fire to relax where he can also complete The Times' crossword puzzle. Laura responds: "You have the most peculiar ideas of relaxation."
- 1948: The Crossword Puzzle Mystery (radio show), serial The Adventures of Superman