The Americano is one of the few cocktails older than the Negroni — equal parts Campari and sweet vermouth, topped with soda water and a wedge of orange. Gaspare Campari created the bitter aperitif that bears his name in Milan in 1860; sweet vermouth came from Turin; the cocktail combining them was originally called the Milano-Torino. By the early 1900s American tourists were ordering it so enthusiastically that bartenders started calling it after them.
The drink came first; the gin variation came later. The Negroni is an Americano with gin.
Older Than the Negroni
Gaspare Campari opened his café-bar in Milan in 1867 and was selling his bitter red aperitif by then; sweet vermouth (most often Cinzano or Carpano from Turin) had been a Piedmontese specialty since the late 18th century. Combining them — equal parts, with soda — was a standard 19th-century Italian aperitivo by the 1860s. The cocktail's first widely cited print appearance under the "Americano" name comes in the early 20th century; the Milano-Torino name predates it.
The Negroni story — Count Camillo Negroni asking a bartender in Florence to make his Americano stronger by swapping the soda for gin, around 1919 — is the canonical origin myth. The cocktail genealogy runs Americano → Negroni → Boulevardier → Old Pal, each one a single-ingredient variation on the one before it.
The Spec
Equal parts Campari and sweet vermouth — about an ounce and a half of each — built directly in a highball glass over ice, topped with three to four ounces of cold soda water and stirred gently. An orange wedge or peel, depending on the bar's house style. No shaking, no straining.
Sweet Vermouth Matters
Cinzano Rosso is the historically authentic choice for an Italian aperitivo. Carpano Antica is richer and more vanilla-forward, suited to drinks where the vermouth is meant to be tasted distinctly (a Boulevardier, a Hanky Panky). For an Americano, Cinzano or Punt e Mes keep the drink from getting heavy.
Build in the Glass, Not the Shaker
The Americano is a built drink — Campari, sweet vermouth, ice, soda, stir. Shaking it would aerate the soda away and overdilute the spirits. The point of an aperitivo is low ABV, slow drinking, and a clean profile; the build method preserves all three.
Orange Wedge vs Peel
Either works. A wedge gives a small amount of juice as the drink rests; a peel expressed over the surface gives oils without juice. The historically authentic Italian bar-room move is the wedge; the modern cocktail-bar move is the peel.
Bottom Line
The Americano is the answer for late-afternoon drinking, when something stronger would be too much. Lower ABV than its descendants, refreshing in a way they aren't, and the cocktail that explains how the Negroni came to exist. Make one and a Negroni back-to-back; the family resemblance is the entire point.