Noilly Prat is a brand of dry and sweet vermouth based in the southern French town of Marsellian. It was bought in 1971 by Martini & Rossi, and is now bottled by that company, though production remains in Marsellian.
Noilly Prat is famous for inventing the dry (French) style of Vermouth. The process was invented in 1813 by Joseph Noilly, but the company was founded in 1855 by son in law Claudius Prat and his son Louis. After their deaths in 1859 and 1865 respectively, Louis' daughter Anne (who was the widow of Claudius) ran the company for forty years until her death in 1902, growing Noilly Prat into an international brand. Her sons Louis and Jean ran the company until 1939, when control was passed to his neice, Viscountess Vigier. She was the last family member to run the company, and sold it to Martini & Rossi in 1971.
Noilly Prat Dry is famous for being the vermouth called for in both the 1896 "Marguerite" cocktail (2 gin :1 vermouth), and in the 1911 Knickerbocker hotel Martini (where it was 1:1 with gin).
Noilly Prat Dry is made from local white grape varietals, such as Clairette and Picpoul, which are mainly desired for their acidity. The wine is aged in large Canadian oak barrels for eight months before being transferred to smaller barrels and moved outside for a year with no temperature control. This oxidizes and stabilizes the wine, while imparting flavor from oak and concentration due to evaporation from extreme temperatures. After a year, the barrels are taken back inside, where mistelle (a blend of brandy and grape juice) is added, along with a secret blend of herbs and spices (said to include chamomile, bitter orange peel, centaury, coriander, cloves and nutmeg), which are infused for three weeks. This is filtered, and after six more weeks of rest, is shipped to Martini & Rossi for bottling.
Noilly Prat also makes a red (sweet) and an amber vermouth. The red was invented in the 1960's, and includes 30 flavoring and coloring agents. Most of Noilly Sweet is exported to the United States. The amber was released in the 1980's, and was originally only sold at the winery, though it is now in wider release.