Cask finishing is hardly new in the whiskey business. Name a barrel type — French oak, Mizunara, Amburana, ex-sherry, ex-port, ex-Madeira — and, most assuredly, some bourbon, rye, or Scotch has spent the final period of its maturation in it.

While not as popular as Spanish and Portuguese fortified wine casks, rum barrel finishing is hardly atypical, either, with brands like Balvenie (The Caribbean Cask 14) and Angel’s Envy (Rye Finished in Caribbean Rum Casks) even making such expressions part of their core lineups. And yet, it’s nearly impossible to think of a rum brand that’s literally called out by name when used as a whiskey finishing barrel.

Then there’s Foursquare, which, in many recent cases, gets the same billing on product labels as the whiskey brands being allowed to finish their products in the Barbadian rum casks. In fact, one could argue, Foursquare’s involvement is the key reason people care about these releases.

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Transformation of the Spirit

Take the most recent Singular Limited Release No. 7 from High N’ Wicked.

That brand was founded by two former Brown-Forman executives, W. L. Lyons Brown III and Kevin E. Sachs, who didn’t want to simply source whiskey, but instead create a brand centered on provenance and transparency.

They contract distilled with New Riff and early releases included flagship expressions like a 5-year-old sour mash Kentucky straight rye (the source for thier 5-year-old sweet mash Kentucky straight bourbon is undisclosed).

“We also wanted to have these little one-off things that speak to provenance, that speak to unique sourcing and the transformation of the spirit, too,” explains Brandon Cummins, director of education at Altamar Brands, which maintains High N’ Wicked within its portfolio.

Enter the “Singular Limited Releases” line, which initially included The Judge, a 14-year-old straight bourbon finished in ex-Hungarian Tokaji casks, and The Jury, a 15-year-old bourbon finished in ex-Tinta Negra Madeira casks.

Eventually, the brand decided to add an Irish whiskey component to its growing line and, luckily, was able to enlist Noel Sweeney to spearhead the project. The longtime master distiller (previously with Cooley and Powerscourt Distilleries) had recently secured lots of interesting stocks that he thought might make for good limited releases.

“With every new Exceptional Cask release they are practically pre-sold before the container even hits the United States.”

One such stock just so happened to be an incredible single grain Irish whiskey, mostly composed of corn. Sweeney believed it was at an ideal age to put in a finishing barrel and he specifically thought it would fare very well with an ex-rum cask.

Luckily, the folks at Altamar knew the perfect brand to work with. Because they already had it in their portfolio.

Exceptional Casks

Often described as “the Pappy of rum,” Foursquare has become a cult sensation within the last decade. But it wasn’t always that way.

The distillery is located in Barbados, opened in 1996 on a former sugar plantation dating back to the early 18th century. Its owner, blender, and distiller is Richard Seale, a fourth-generation rum producer.

By 1926 the Seale family was buying rum from other Barbados distilleries, which they would blend and then sell under the R. L. Seale label. In the early ’90s, Richard Seale and his father began renovating a shuttered sugar factory into the distillery it is today. His vision from the start was to produce “honest” rum, unadulterated with no added sugars or flavoring.

It was a quiet brand at first, not really known among anyone but the most ardent rum connoisseurs. That all started to change in 2009 when Seale launched the Exceptional Cask Series, hand-selecting his most unique and rare barrels for bottlings. By the 2014 releases of Port Cask Finish and Zinfandel Cask Finish expressions, Foursquare had begun to garner a cult following. By 2016’s release of 2004, a rum completely aged in ex-bourbon casks, Foursquare was suddenly on whiskey geeks’ radars and stores couldn’t keep product on hand.

“The irony was that when we started this conversation with Richard, we thought that, ‘Oh, wow, we’re going to be the first people finishing whiskey in some Foursquare casks. Unbeknownst to us, he had also relinquished some barrels here and there to a few other distillers and blenders that he also regarded.”

Altamar has been the importer of Foursquare since the early days and seen firsthand the brand’s meteoric rise.

“I remember back, actually, about eight, nine years ago when we first started importing the Exceptional Casks. The first releases took nearly three years to sell through,” says Cummins. “Now with every new Exceptional Cask release they are practically pre-sold before the container even hits the United States.”

Altamar introduced Sweeney to Seale and asked if it was possible to get some barrels specifically from the Exceptional Cask line.

Seale surprised them by offering Sweeney barrels that had previously held Mark X – 2007 Finish, a 12-year-old, cask-strength release. The barrels were taken back to Ireland, filled with the single-grain whiskey, and left to mature another six months or so. Cummins says that Seale didn’t get to sign off on the final product, so he had to trust that what Sweeney and High N’ Wicked were producing would befit the lofty Foursquare name.

“The irony was that when we started this conversation with Richard, we thought that, ‘Oh, wow, we’re going to be the first people finishing whiskey in some Foursquare casks,’” Cummins says. “Unbeknownst to us, he had also relinquished some barrels here and there to a few other distillers and blenders that he also regarded.”

Collaborative and Collaboration

“We were the first co-branded collaboration with Foursquare that I know of,” says Dan Callaway, Bardstown Bourbon Company’s (BBC) vice-president of product development

Last April BBC released a custom blend of 7-year-old rye and 17-year-old bourbon finished in Foursquare barrels for an additional 23 months. As part of the Collaborative Series — which has also featured finishing barrels from Goose Island Bourbon County Brand Stout and Amaro Nonino — the Foursquare logo was displayed prominently on the label.

“I have wanted to partner with Foursquare from day one,” Callaway says. “I’m a huge fan of their rums, but most importantly, their values of innovation, authenticity, and transparency align perfectly with [us].”

Having no contacts there, Callaway simply DMed Richard’s wife Gayle Seale on Instagram. He eventually convinced the Seales to send 150 used rum barrels from Barbados to Bardstown. Callaway claims there was no contract or money involved, “it was built 100 percent on trust.”

I thought it was spectacular, perfectly balanced between rye spice, caramel sweetness, and tropical notes; neither the whiskey nor rum duking it out for supremacy. And apparently, many bourbon geeks were eager to try it as well. Despite a $159.99 price tag, it sold out within hours when it was offered on the online retailer Seelbachs.com.

Bardstown Bourbon Company isn’t the only trendy U.S. whiskey brand enamored by Foursquare. Buzzy American whiskey bottler Rare Character has also released Foursquare-finished single barrels. Colorado Springs-based distillery Art of the Spirits has likewise Foursquare-finished a cask strength “bou-rye” release.

“It’s intriguing to see the character our rum casks will impart on the blend and it’s an excellent opportunity to engage whisky drinkers to bring them into the world of rum.”

In October 2023, the Isle of Skye-based Scotch distillery Mossburn released what it dubbed Mossburn x Foursquare, the first in what the producer claimed would be an annual Cask Collaboration Series. The brand took its classic Speyside single malt, aged 12 years, and matured it for a little longer in American oak casks that had previously held Foursquare.

“When [Mossburn’s whisky maker] Neil [Macleod Mathieson] asked if we could collaborate on aging his whisky in Foursquare casks, I was immediately keen to be involved,” Seale claimed, upon the release of the product. “It’s intriguing to see the character our rum casks will impart on the blend and it’s an excellent opportunity to engage whisky drinkers to bring them into the world of rum.”

A Win-Win

This trend reminds me of a trend about a decade ago, when seemingly every brewery was trying to raise its own bona fides by aging its stouts and barleywines in ex-Pappy Van Winkle barrels. With Pappy barrels a near impossibility to source these days, though, it seems Foursquare finishing has been the new way to add hype to your product.

And that kinda seems to be the point of this whole fad: a win-win situation for both Foursquare and the whiskey brands it works with. Whiskey brands get to ride the coattails of the most coveted rum in the game and elevate their own standing.

“Selfishly, absolutely,” Cummins jokes when I ask him about that.

Meanwhile Foursquare gets to introduce itself to even more whiskey fans — but don’t go thinking you can launch the next hyped whiskey brand without talking to Richard Seale first.

“We don’t allow our name or logo to be used without express permission,” he warns me.