The Rob Roy is the Scotch-based variation of the Manhattan named after Scottish folk hero Rob Roy.
The cocktail combines Scotch whisky, sweet vermouth and bitters, following the basic structure of a Manhattan while changing the base spirit. It is usually stirred with ice and served up, often with a cherry. Some recipes distinguish sweet, dry and perfect Rob Roys according to the vermouth used.
The name refers to Rob Roy MacGregor, a Scottish outlaw and folk hero whose life inspired the 1894 operetta Rob Roy. The cocktail appeared in connection with that stage production in New York, although exact early documentation is limited.
A Rob Roy is not simply any Scotch cocktail. The recognizable Manhattan relationship comes from the combination of whisky, vermouth and bitters. A Rusty Nail, by contrast, combines Scotch with Drambuie and has a sweeter liqueur-based profile.