What was the main cause of the 1911 Champagne winegrowers’ revolts?

The main cause of the 1911 Champagne winegrowers’ revolts was the use of imported grapes by Champagne merchants.

Winegrowers in the Marne objected when négociants bought grapes from outside the traditional Champagne growing area, particularly from the Aube and other regions, to make wines sold as Champagne. They feared that outside fruit would depress prices and damage the identity of the regional product.

The unrest involved protests, destruction of wine and property, and intervention by the French authorities. The dispute exposed a central problem in Champagne: who was entitled to supply fruit for a wine using the region’s name.

The crisis helped drive later efforts to define the geographical boundaries and rules of the Champagne appellation. It was not primarily a dispute about grape colour, bottle supply or overseas taxation.