While there is nothing original about the commodity history, there have been dozens of book in the last decade that chronicle the fate of just one commodity in history, Rum is a particularly fun spin on the genre and has the added benefit of providing some little known facts about the history of this delicious libation. One distinct advantage that Rum has over other books in its genre is its subject matter tends to be connected to more colorful historical incidents and characters than other commodity books have dealt with (Salt, by Mark Kurlansky, leaps to mind with its interminable chapter on Gandhi.)
Rum charts the history of the spirit from its invention to the present and all throughout presents the standard thesis of the commodity book, "man, Rum sure was important at many different times and places." What is nice is that in this case the thesis has the virtue of actually being valid. It seems that without the high demand for sugar, most of it in the form of rum, the slave trade between Africa and the Caribbean Islands would never have reached its height, and the histories of at least two continents would be very different today.
Williams also places rum in its proper place in American history, as perhaps the most distinctly American spirit. While whiskey, particularly bourbon, may have surpassed rum in the modern mind as the American liquor of choice, it was rum that was quite literally the "Spirit of '76" when America's founders were known for quaffing the stuff quite liberally.
Rum is exactly the kind of history that most people want to read, straddling the line between gossip (Washington had an entire cellar for storing his rum?) and hard history. At the same time it shares the flaw of almost all commodity histories in that it often tries to overstate its own case for the distinctive importance of its subject, which can mean that it loses some of the power it might have had. If anything rum provides an entertaining foray into a little known branch of history, that shouldn't be missed.