It is fairly well known that, according to the generally accepted history of the puzzles, crosswords were first created in the USA in 1913 and crossed the Atlantic to Great Britain some eleven years later. In fact, a study of much of literature shows this to be false, and reveals innumerable earlier references to crosswords. The works of William Shakespeare provide a particularly rich source of such allusions.
Word Ways: Vol. 12
, Article 12.
Available at: http://digitalcommons.butler.edu/wordways/vol12/iss4/12