Pimm's is a brand of liqueurs that was first produced in 1823 by James Pimm. The most commonly available product of the brand is the Pimm's No. 1 Cup.
The Pimm's No. 1 Cup is a gin-based liqueur based on a secret recipe, which includes orange peel and spices. It's generally used in only one beverage, the Pimm's Cup, though bartenders have been known to experiment with it.
Pimm, a farmer's son from Kent, became the owner of an oyster bar in the City of London, near the Bank of England. He offered a gin-based tonic as an aid to digestion, serving it in a small tankard known as a "No. 1 Cup", hence its subsequent name. Pimm's began large-scale production in 1851 to keep up with sales to other bars. In 1865, Pimm sold the business and the right to use his name to Frederick Sawyer. In 1880, the business was acquired by future Lord Mayor of London Horatio Davies, and a chain of Pimm's Oyster Houses was franchised in 1887.
Over the years, Pimm's extended their range, utilizing a number of other spirits as bases for new "cups." In 1851, Pimm's No. 2 Cup (Scotch-based) and Pimm's No. 3 Cup (brandy-based) were introduced. After World War II, Pimm's No. 4 Cup (rum-based) was invented, followed by Pimm's No. 5 Cup (rye-based) and Pimm's No. 6 Cup (vodka-based) in the 1960s.
The brand fell on hard times in the 1970s and 1980s. The Oyster House chain was sold and Pimm's Cup products Nos. 2 to 5 were phased out due to reduced demand in 1970 after new owners, The Distillers Company, had taken control. The Distillers Company was subsequently purchased by Guinness in 1986 and Pimm's became part of Diageo when Guinness and Grand Metropolitan merged in 1997. In 2005, Pimm's introduced Pimm's Winter Cup, which consists of Pimm's No. 3 Cup (the brandy-based variant) infused with spices and orange peel.