Forever at war with the silly idea that the main way to categorize the types of rum is by color (light, gold and dark) instead of by flavor (traditional, light and blended), I post this excerpt from the eighth volume of the West Indian Bulletin, published in 1907, that makes clear that the term “light rum” before prohibition was used to refer to rum that was light in flavor due to distillation method and short fermentation.
The source is describing the growing rarity of old (aged beyond 6 or 7 years) flavorful, pot-still rum. To conceptualize what he means by “old rums of delicate softened flavour,” taste both Wray & Nephew White Overproof Jamaica rum and then Smith & Cross Traditional Jamaica Rum. They both are clearly pot-still character, traditional rums, in that the flavor of molasses is clearly evident in a way unlike in any light rum. The effects of the additional aging in the Smith & Cross are what the source means by “delicate softened flavour.” This should not be taken as a description of light rum. The source then states that most rums he now encounters in Jamaica are blended rums.
Note that the source also clearly understands that lighter rums take on the flavor of the barrel much faster (without the flavor of molasses to overcome). The suggestion is that in pubs, a less-expensive rum that was mostly made of light rum and that tasted woody and expensive after a shorter time in the barrel was desired by the pub owners.
In order to make blended rum, light rum is needed and the source describes what production methods make light rum ‘light.’
This is not about color. The wood-flavor added as a consequence of aging cannot transform light rum into traditional rum. It just becomes light rum with a bit of woody flavor – not traditional rum with a bit of woody flavor. Havana Club 7-year old Cuban rum does not taste like traditional rum – it tastes like old light rum. El Dorado 15-year old Demerara rum tastes like old traditional rum. The point in the excerpt from 1907 is that by doing a shorter fermentation and then distilling more efficiently – that is closer to pure ethanol than a pot still can achieve – rum is produced that is lighter in flavor.
I suppose it’s the fault of the English language that both old words léoht (as in sunlight) and liht or lith (as in ‘lithe’ or un-heavy) are now expressed in the same spelling: “light.”
American bartenders seem to have understood around 1910 that Cuban rum (even the aged, brown stuff) was called ‘light’ because it was produced to be lighter in flavor than the more traditional rums they were accustomed to. But, the masses of suddenly-hired, completely-untrained post-repeal bartenders never seemed to have learned that the phrase “light Cuban rum” was not originally meant to refer to the color of the cheapest, colorless Bacardi bottling they all had at their fingertips in 1934.
For proof that Cuban rum-men still have the understanding that their rum is light, even the 7-year stuff, watch the “Hooray for Havana Rum!” episode of the Thirsty Traveler. In that episode the master distiller of Havana Club tells Kevin Brauch, “All Cuban rums are light.”
Now, tell your friends to stop using their eyes to categorize rum, and to start using their taste buds for that purpose!