The first-ever crossword puzzle, created by British journalist Arthur Wynne, ran on December 21, 1913—the eve of World War I—in the “Fun” section of New York World newspaper. As the war progressed, the paper dialed up advertising efforts to the puzzle as a reprieve from increasingly bleak headlines. On the 109th anniversary of the modern-day crossword puzzle, put your thinking cap on and find solace with the most recent McKinsey Crossword puzzles.