Which French region gives its name to true sparkling champagne?

Champagne, and the protection of that name is one of the most aggressively defended pieces of intellectual property anywhere - the region's trade body pursues cases worldwide over sparkling wine, over sorbet, over perfume, over a village in Switzerland called Champagne which was ordered to stop putting its own name on its still wine.

The bubbles began as a defect. Bottling before fermentation had finished trapped carbon dioxide, and bottles exploded in the cellars - one going off could set off a chain reaction, and cellar workers wore iron masks. Dom Pérignon, a monk usually credited with inventing champagne, spent much of his career trying to prevent the bubbles, which he regarded as a fault.

The English probably made it deliberate first. English glass, made in coal-fired furnaces, was stronger than French wood-fired glass and could hold the pressure, and English drinkers were adding sugar to induce a second fermentation decades before the French method was systematised. A paper describing how to make wine sparkle was presented to the Royal Society in 1662, some thirty years before the French claim - which is the sort of fact that does not travel well in Reims.