Brand: Foursquare, Exceptional Cask Selection series

Origin: Foursquare, St. Philip, Barbados

Still: Pot & Column Blend

Age: 17 years

Finish: ex-Bourbon

ABV: 58%

The tri-annual Exceptional Cask Selection (ECS) releases from Foursquare are known to have 3 main components: a vocabulary lesson, a limited release of bottles, and, of course, delicious, unadulterated rum. The 20th installment of this series is no exception.

Isonomy ("equality under the law") is indeed mark XX in the sequence, and follows closely behind the previous release, Sovereignty. For this milestone, Foursquare owner and Master Blender Richard Seale decided to dig into his rum stock and select long-aged barrels for blending, which becomes their oldest distillery release yet.

I was lucky enough to try Isonomy while touring Foursquare's facilities with my girlfriend earlier this summer; Gayle Seale was gracious enough to offer us a tour, and later, a private tasting of some new and rare rums, including Sovereignty, Isonomy, and the Velier Magnum Foursquare bottling. Isonomy stood out to me, and gave me a desire to secure a bottle when it made its way to the US.

Foursquare Isonomy is a blend of pot still and column still rums, which were aged exclusively in ex-Bourbon barrels for no less than 17 years. What I've heard about this long-aging process (from other rum enthusiasts) is that as the aging progresses, increasingly neutral casks are used to house the original distillate, to ensure the end product does not carry too much oak influence. The rum was bottled at 58% ABV, without any additives.

Because this release uses an undisclosed number of barrels of old stock, it is exceedingly limited in the amount of bottles yielded, with an estimate of only 3,000 bottles globally. I was able to get this bottle thanks to Pete Cope of the DFW Rum Club, and I look forward to sharing my notes with the community.


Golden brown with an orange hue, medium clarity, medium viscosity


Vanilla, butterscotch, permanent marker, dark chocolate, stewed strawberries, pastry dough, brown sugar


Pastry dough, vanilla, crisp red apples, nutmeg, brown sugar, graham crackers, butterscotch


Medium-long, warming; oak, sour apple, bitter chocolate, black cherries

Rating: 7/10


Isonomy is a really special installment of the ECS series, and shows that even after nearly 2 decades of aging, Foursquare's signature notes can still be captured masterfully. The notes and experience of Isonomy are very close to one of my favorite ECS releases, the 2009 vintage, but really amps up some of those shared notes even more; in some ways, it works, in others, not so much.

In the glass, Isonomy is a nice golden brown color, tinged with an orange hue; it has medium clarity and medium viscosity. It is not quite as viscous as other, more recently reviewed rums, despite being relatively close in age; perhaps the aforementioned casking regimen used in this blend has something to do with it.

The nose offers notes of vanilla, butterscotch, permanent marker, a higher-cocoa dark chocolate, stewed strawberries, pastry dough, and brown sugar. Lot's going on here, and this is really reminiscent of the 2009 nose, but boosted; it's really lovely, and just screams "Foursquare". Knowing that some ex-Bourbon releases can have different nosing experiences, I'm a tad disappointed that Isonomy doesn't have something a little more unique to the nose. All-in-all, the nose is incredible, and one that you could really sit with for hours.

Sipping Isonomy yields notes of pastry dough, vanilla, crisp red apples, nutmeg, brown sugar, graham crackers, and butterscotch. Again, Foursquare notes abound, bringing with them some delicious apple notes, some nutmeg spice, and more savory elements like brown sugar and graham crackers. Definitely less fruity than the previously-reviewed Sovereignty, but again really showcasing the notes that ex-Bourbon-aged vintage releases are known for. The standout here is the brown sugar, which is a nice complimentary flavor to the vanilla and butterscotch.

The finish is medium-long and warming. Plenty of oak, some sour apple, bitter chocolate, and black cherry notes come through as the finish progresses. Honestly, it's not my favorite finish that I've had from an ECS release, with a lot of bitterness coming through after the initial warmth and slight fruity notes die off. Undoubtedly, this is due to the long aging, but does negatively impact the experience slightly.

If you liked 2009, you'll likely enjoy Isonomy; if you didn't, you probably won't. While I'm glad the 20th ECS release was marked with a truly exceptional blend of 17 year old rums, I would question if using such long-aged rums is a scalable strategy for future ECS releases, given the limited bottle yield and the high price of Isonomy. As it is, finding Foursquare ECS bottles on the shelf can be enough of a challenge, and they are some of the highest-priced (though often matched with value) distillery-released rums on the market.

My verdict: this is a really great rum that shows the longevity of Foursquare's rums and processes, even if it has some aspects that aren't perfect.

Further Reading