The 1960s Handbook takes a closer look at the cultural references that appear in each week's episode of Mad Men.

"New! A sugar-free cola with rewarding true-cola taste!" That was the message sent to American housewives in 1963 when they opened their newspapers to advertisements that fired the first shots in the diet cola wars. This particular smoking gun belonged to Patio Diet Cola, Pepsi's first entry into a market already occupied by Coca-Cola's Tab and then-powerhouse Royal Crown Cola's Diet Rite.

What had begun as a soft drink alternative for diabetics in the '50s exploded into a full-blown diet craze a decade later. Patio redefined the conversation by aiming its marketing squarely at weight-conscious women via ads depicting svelte spokeswoman Debbie Drake assuming acrobatic poses while explaining how gals could maintain their figure through proper diet and exercise. ("Great to your waist!" "The refreshing way to stay slim!")

In no time at all, Pepsi thereby changed the diet cola conversation. "All of the leading diet colas are practically alike," Pepsi declared. "They look alike. They're all sugar-free. And they all have but one tiny calorie to the glass. The only real difference is taste!" (This same argument continues today.)

So how is it that marketers haven't spent the past 50 years challenging Coke drinkers to take the "Patio Challenge"? Because in 1963 a former syrup sales representative named Donald Kendall became CEO of Pepsi-Cola. Eschewing the notion that diet sodas should be distanced from their caloric counterparts, Kendall rebranded Patio Diet Cola as Diet Pepsi. The gamble paid off: Diet Pepsi became so popular that Coca-Cola was eventually forced to all but abandon Tab in favor of Diet Coke.

Not that the Patio brand vanished forever. Flavors like Strawberry Cream and Root Beer persisted into the '70s. Indeed, you can still find Patio sodas today, lurking behind bar taps as a fountain Ginger Ale and Quinine Tonic. As for Debbie Drake, her fame appears to have faded completely.