Don Draper may prefer Canadian rye, but even Irish whiskey is profiting from Mad Men's whiskey-boosting effect. (AMC)

Prohibition in America cut one of Irish whiskey's final lifelines. The industry had already been weakened by Ireland’s own national temperance movement, the rise of Scotch whiskey, and a trade embargo from England. By 1972, only four distilleries remained, all controlled by one company.

Now, driven in part by American consumer interest, Irish whiskey is finally recovering from its five decades of relative obscurity to become the world’s fastest-growing spirit. In the U.S. alone, sales have grown 400% since 2002 and 22.5% in the last year, according to the Distilled Spirits Council of the United States (DISCUS). Compare that to a 13.5% sales increase in a year for single malt Scotch whiskey, the second-fastest growing category.

Until recently, most of the Irish whiskey I had consumed was Jameson, that ubiquitous brown liquor most often consumed in a shot glass or mixed with soda — a smoother, more palatable alternative to Jack Daniels or Johnnie Walker, but not in the same league as many single-malt scotches or small-batch bourbons.

Then, on a recent trip to Dublin, I had my first glass of Green Spot, a pot-still whiskey, the style that once made Ireland the world’s most respected whiskey producer. It was smooth without giving up anything in the way of flavor and complex without being difficult to appreciate. Unlike most bourbon and scotch, which are usually double distilled, Irish whiskey is generally triple distilled, which gives it a sweeter, fruitier nose and an incredibly smooth taste and mouthfeel. Brendan Buckley, the Innovation & Category Development Director for Irish Distillers, believes it’s this smoothness that may have helped Irish whiskey grow: It’s easier for a novice whiskey drinker to appreciate than some of the more complex Scotch whiskeys.

During a week in Ireland, I journeyed down the rabbit hole, sampling a dram of every local whiskey I could get my hands on, and discovered that Irish whiskey could go toe to toe in the ring with the best scotch or bourbon. I, like most other Americans, had just been drinking the wrong Irish whiskey.

It’s not our fault, of course. Until the last few years, Jameson and similarly priced competitors like Bushmills and Tullamore Dew were all that was available.

Yet even Jameson’s widespread availability is a relatively new development. For much of the twentieth century, Irish whiskey was a drink mostly enjoyed by Irish immigrants in the US, frequently as a little spike for Irish coffee. But when spirits giant Pernod Ricard took over the Jameson-producing Irish Distillers in 1988, it removed Irish Distillers’ other brands from US shelves and used its wide-reaching distribution network and a massive marketing campaign to turn Jameson into an international powerhouse. Jameson still controls the vast majority of the global Irish whiskey market. To keep up with demand, Irish Distillers just finished a €100m expansion of its distillery in Midleton that will allow it to nearly double capacity.

The cause of the current renaissance of Irish whiskey—and in particular the proliferation of super-premium options—is more opaque.

Irish whiskey’s fate has always been tied to the whims of US drinkers, and just like American prohibition helped to cripple the industry in Ireland, American demand is largely responsible for reviving it. The cocktail renaissance that began in the early 2000s is probably one factor in the popularity growth of American whiskey, which in turn helped create a growing market for Irish whiskey.

Classic cocktails and the craft of bartending virtually died with Prohibition. Its revival is widely credited to Dale DeGroff, who began using fresh produce and a more culinary approach to cocktails at New York’s Rainbow Room in the late 1980s. But it wasn’t until the early 2000s when the use of fresh, innovative ingredients spread across the country. Soon, bartenders were digging through antiquated cocktail books in search of recipes from before prohibition — when bartending was still an art form. None of those recipes included vodka, a spirit that wasn’t popular in the US until well after prohibition ended. But many included whiskey, and soon hand-crafted whiskey drinks were replacing cloying vodka drinks like appletinis at serious cocktail bars nationwide.

Preferences — particularly among young drinkers in the US — have begun to shift from clear spirits to brown liquors. While vodka is still by far the most popular spirit in the US, the growth rate of its sales volume has declined each year since 2010, while gin has actually decreased in popularity. The amount of whiskey purchased has increased every year in the same period, and in 2012, whiskey finally outpaced vodka, growing by 5.1% compared to vodka’s 4% growth. This trend is commonly referred to as the “Mad Men Effect”, because it’s partially driven by whiskey’s larger presence in pop culture and big-name television shows like Mad Men, similar to the way Sex and the City popularized the cosmopolitan. Irish whiskey in particular is just starting to find its way into mixed drinks, having spent most of its long history in a glass with no company save a few drops of water or some ice.

In response to rising demand, the number of super-premium Irish whiskey brands available has skyrocketed. Numbers from DISCUS show super-premium Irish whiskey sales in the U.S. have grown more than 1,700% in the last decade, and a staggering 82.6% in the last year. The slow food and craft beer movements of the last two decades have created more discerning palates, eventually extending to the spirits category and resulting in a huge rise in single-malt scotch and artisanal, small-batch bourbon. As Americans started exploring the world of high-end bourbons and scotches, it paved a path for super-premium Irish whiskey to enter the scene.

The Cooley Distillery, which started distilling in 1989, also played a large role in the revolution. Cooley helped raise the bar in quality by resurrecting old brands and making styles rare in Ireland, like single-malt The Tyrconnell, which dates back to 1972, and Connemara, the country’s only peated whiskey. Until then, peated and single-malt whiskies belonged almost exclusively to Scotland. But Ireland had an equally delicious and equally unique style of its own: pot-still whiskey.

Pot-still whiskey is made in a copper pot still from a combination of malted and unmalted barley from one distiller. At one time, pot-still whiskey (also called single pot-still or pure pot-still) wasn’t just the most cherished style in Ireland. It was the only style.

Yet, due to high costs and a lengthy process, pot-still whiskey virtually died in the world. Green Spot and Redbreast, both made at Midleton Distillery, are the only single pots to have survived throughout their history. Midleton has since resurrected Yellow Spot with great success in Ireland. Green Spot will not be available in the US until 2014 and Yellow Spot likely not until at least 2015.

According to Buckley, demand far outweighs supply, so it can still be difficult for US consumers to find the best bottles anywhere but specialty stores or bars.

The shortage is a result of long lead times—the minimum legal aging requirement for Irish is three years, but the highest quality whiskies age in barrels for at least 8 years. It’s not easy planning for demand more than eight years in advance, so it could still be awhile before there is enough super-premium Irish whiskey to meet American thirst.

But that also means that we’re still far from reaching the peak of Irish whiskey. Cooley and Kilbeggan distilleries both have single-pot whiskies sleeping in barrels and awaiting release, and for the first time since Cooley began distilling in 1989, a new crop of distilleries are opening across the Emerald Isle. There are still only four distillers with matured stock, but craft distillers Dingle, Alltech and Echlinville — currently the only Irish-owned distilleries, since Jim Beam bought Cooley in 2012 — began production in 2012 and 2013. It won’t be until at least 2015 when any of these distilleries release bottles. But already, American drinkers—and the Irish producers supplying them—are seeing an array of options their grandparents would have found inconceivable.