Treaty of Turin

The Treaty of Turin concluded between France and Piedmont-Sardinia on March 24, 1860 is the instrument by which the Duchy of Savoy and the County of Nice were annexed to France.

Emperor Napoleon III of France and the Count of Cavour, Prime Minister of the Kingdom of Sardinia, met in secret at Plombières-les-Bains on 21 July 1858. They agreed that France would support the unification of Italy by Sardinia, provided that the Pope should retain control of Rome. In return Sardinia was asked to cede the Duchy of Savoy to France along with, more contentiously, the predominantly Italian speaking County of Nice.

In April 1859, Austria, complaining that Sardinia had been supplying arms to Lombard separatists, declared war on Sardinia. The Franco-Sardinian forces defeated the Austrians in several battles: Palestro, Montebello, Magenta, and Solferino.

But Napoleon III, who had taken personal command of his army, professed himself horrified by the extent of the bloodshed involved and resolved to end the war. The fighting ended with the armistice of Villafranca on 12 July 1859. The armistice led to the Treaty of Zurich of 10 November 1859, which transferred Lombardy to Sardinia. Complete Italian unification was deferred, though as matters turned out, not for long.

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