The Boulevardier cocktail is a lesser-known cousin of the Negroni cocktail. The drink is made with a Bourbon or Rye Whiskey, Campari and Sweet Vermouth and is believed to have been created in the 1920s by an American expatriate living in Paris. The Boulevardier has recently experienced a resurgence in popularity among cocktail enthusiasts and has been featured on many high-end bar menus, books and articles around the world.
This is after a similar drink, the "Old Pal," appeared in the same category but uses Canadian Club whisky instead of bourbon. The Old Pal became more well-known over time and the Boulevardier was mostly forgotten.