As a bartender you become familiar with the usual suspects.  These key players - vodka, gin, rum, tequila, whiskey, brandy, and scotch - form the foundation upon which most modern cocktails are built.   Supporting these base spirits are a vast array of lesser known and exotic bit players - cordials, liqueurs, fortified wines - the list goes on and on.  Perhaps the most underappreciated of these is vermouth.  Although vermouth maintains its necessity by virtue of its inclusion in several important cocktail classics, it is largely unknown and unloved in its own right.  This has not always been the case.  Early mixologists relied heavily upon vermouth as a central component of their creations.  Among its desirable qualities were its abilities to accentuate flavors, to introduce aromatics, and to mitigate the high alcohol content of other ingredients.
 
Today, in the era of the “extra dry” vodka martini, very few people even know what vermouth is.  Vermouth is, in fact, a fortified wine.  Like both sherry and port vermouth begins as a wine base to which a distilled spirit is added.  This both increases the alcohol content and the shelf life of the final product (an important feature in the days before refrigeration).  Vermouth also qualifies as an “aromatized” wine, meaning it has been infused with a selection of herbs and spices.  Historically this served the purpose of masking unpleasant odors and flavors present in mediocre wine.  One of the main flavoring agents in early vermouth was wormwood - in fact it is the German word for this ingredient from which the name “vermouth” is derived.  Since those days wormwood has fallen out of favor, largely because it was suspected of being poisonous.  Modern vermouth is infused with any number of dry ingredients including cloves, cinnamon, citrus peel, cardamom, marjoram, chamomile, coriander, juniper, hyssop, and ginger.

Americans are most likely to be familiar with the two dominant types of vermouth - sweet and dry (although there are other several other varieties).  The creation of sweet vermouth is credited to Italy’s Antonio Benedetto in 1786, while the dry white version of vermouth was created in the early 1800’s by Joseph Noilly of France.  Early vermouth was largely celebrated for its purported medicinal qualities, wormwood in particular being regarded as a treatment for parasites.  The concoction also came to favor as an apertif, its bitter sweet flavor making it an ideal appetite stimulant.  In the hands of American mixologists vermouth rose to even greater prominence, established as the dominant ingredient in a number of early favorites like the Manhattan, the Negroni, and the Martinez which later became the Martini.

Over the years the use of vermouth in cocktails has dropped significantly.  There are a number of factors to consider.  During Prohibition vermouth was more difficult to acquire than the moonshine and bathtub gin that floated the speakeasies of the time.  As a result the ratio of vermouth used in mixed drinks fell sharply.  Also, as spirit production improved there was less of a need to mask the unpleasant qualities of poorly distilled alcohol.  And perhaps modern drinkers have a greater tolerance for the strong stuff - no need to cut the pure spirit with a less potent vermouth.

Whatever the reasons for its decline, vermouth is poised for a comeback.  Modern mixologists are resurrecting interest in this forgotten player.  Many bars are now stocking premium vermouths and showcasing them in new and inventive cocktails.  It seems that in mixology, like in fashion, that which was old is new again.