The Martini episode was one of those we couldn’t really get a grip on. There isn’t a definitive record of its creation and there was a lot going on at the time that muddy the historical record.
If we just look at earliest mentions of the drink with the name associated with the commonly accepted ingredients for the early Martini we find the earliest article, one that suggests the drink as relatively new and growing in popularity, in the Washington Post, April 12, 1891
However, if we just go with the name we find a recipe for a drink called the Martini in Harry Johnson’s 1888 recipe book but it adds curacao and some gum syrup, but otherwise the other ingredients loosely match the recipe from 1891
But Harry Johnson’s recipe is actually more similar to another drink that was popular at the time…the Martinez. Earliest mention of the Martinez we found was in St. Paul daily Globe. (Saint Paul, Minn.), 20 Nov. 1887 and the drink was commonly described as a Manhattan with gin instead of whiskey.
So did the Martini derive as an offshoot of the Martinez? The timeline is all very tight and circumstantially the dates are close enough that it is probable and makes sense, but we don’t have any evidence to confirm this. We can tell where the Martini fits in the timeline so we know basically when it first came around, but we don’t have a solid origin story for this.
Addendum: In our conversation with Doug Stailey he pointed out another origin story for the Martini involving a New York guy named Frank Martine. Mr. Martine’s obituary in 1891 claims he was the inventor of the drink. Martine wasn’t a bartender. He was more of a man about town who like many of his chums spent his evenings in cocktail bars. The only aspect of the story that stands out is the date. He died in 1891 at the age of 47. If he divined a Martini in the mid 1880s there was plenty of time for it to become popular before he passed. It’s possible. It’s compelling, but not really any evidence to support it.