During the 19th century Peruvian wine-making went further into decline. Demand in industrialized Europe caused many Peruvian winegrowers to shift the land use from vineyards to lucrative cotton fields, contributing further to the decline of the wine and pisco industry. This was particularly true during the time of the American Civil War (1861–1865) when the cotton prices skyrocketed due to the Blockade of the South and its cotton fields. Also in South Africa did wine making suffer a stunning blow in the 1860s with the implementation of the Cobden–Chevalier Treaty in 1860 that forced South African wines to compete with French wines in Britain and resulted a doubling of French wine imports to Britain. South African vineyards also suffered a second setback after the arrival of the Phylloxera plague in the 1880s.