Sabrage

Sabrage /səˈbrɑːʒ/ is a technique for opening a champagne bottle with a saber, used for ceremonial occasions. The wielder slides the saber along the body of the bottle to break the top of the neck away, leaving the neck of the bottle open and ready to pour. The force of the blunt side of the blade hitting the lip breaks the glass to separate the collar from the neck of the bottle. One does not use the sharp side of the blade. The cork and collar remain together after separating from the neck.

The technique became popular in France when the army of Napoleon visited many of the aristocratic domains. It was just after the French Revolution and the saber was the weapon of choice of Napoleon's light cavalry (the Hussars). Napoleon's spectacular victories across all Europe gave them plenty of reason to celebrate. During these parties the cavalry would open the champagne with their sabers. Napoleon, known to have said, "Champagne! In victory one deserves it; in defeat one needs it." may have encouraged this.

There are many stories about this tradition. One of the more spirited tales is that of Madame Clicquot, who had inherited her husband's small champagne house at the age of 27. She used to entertain Napoleon's officers in her vineyard, and as they rode off in the early morning with their complimentary bottle of champagne, they would open it with their saber to impress the rich young widow.

A champagne sword (sabre à champagne) is an instrument specially made for sabrage. Some swords have short blades, around 30 centimetres (12 in) long and resemble large knives, although others have longer blades. The side of the blade used should be blunt – a sharpened edge is unnecessary because in sabrage it is the impact that is important. If using a sword with a sharp blade then the flat blunt back of the blade is used. A champagne bottle can be opened with a spatula using the same method – or the base of a wine glass.

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Wikipedia