There are many stories surrounding the invention of the martini, but it seems that the origins of James Bond's favorite beverage may never be definitively established.

The history of the martini can easily be traced back to the late nineteenth century, when it was first consumed and listed in bartending manuals.  The famous example of this was the drink's appearance in the 1887 manual of bartender Jerry Thomas, of the Occidental Hotel in San Francisco.  This has led to the belief that the drink originated at the hotel bar, possibly as early as the 1860s, where it would have been consumed by travelers heading to the nearby city of Martinez.

However, the city of Martinez has disputed this claim and has listed an alternate story on its website.  It suggests that the drink in fact originated in a prominent bar in Martinez, where it was known as a "Martinez Special." There it was served to a celebrating gold miner on his way to San Francisco, who, after enjoying the drink so much, delivered the recipe to San Francisco when he had to instruct a local bartender on how to make it.

The dispute between these two common theories has even gone beyond passing discussion, as the Court of Historical Review in San Francisco determined that the drink had been concocted in San Francisco.  In return, a court in Martinez overturned this decision.

Yet, others look to the Knickerbocker Hotel in New York, frequented by John D. Rockefeller, as the place of origin of the dry martini, in the early twentieth century. 

It seems safe to say the drink was invented in the middle to late nineteenth century, but exactly who invented the martini is likely to remain the stuff of legend.