It's rare that we can trace a drink's lineage so clearly. The Americano was (and still is) a very popular aperitif cocktail created in Italy, made with Italian (sweet) vermouth, bitter Campari, and soda water.
In 1919 or 1920, Florentine playboy Count Cammillo Negroni came into his favorite watering hole and asked the bartender for something stronger than his usual drink. The bartender replaced the soda water with gin in the Americano and named it after his patron. The Negroni was born. (The recipe here on FineCooking.com is a bit unusual. Typically the drink is made with equal parts gin, Campari, and sweet vermouth.)
Later (so the story goes) a bartender was preparing a Negroni for a cusomer and somehow mistakenly added sparkling wine to the drink instead of gin. This new drink was called the Negroni Sbagliato, meaning 'mistaken' or 'wrong' or 'bungled'. It too is delicious, slightly bitter, and refreshingly bubbly. A delicious mistake.
1 fl. oz. Campari
1 fl. oz. Sweet Italian Vermouth
1-2 fl. oz. Sparkling Wine, such as Prosecco
Pour all ingredients into an ice-filled glass and garnish with an orange wedge.