The National Society was founded in 1857 to promote Italian unification under Piedmontese leadership. Patriotic historiography has emphasised the role of the National Society in the reunification of Italy and presented us with a slightly exaggerated and romanticised view of it.

Gioberti had hoped the Papacy would lead Italy to unification but gave this up in 1851 after the failure of the 1848 revolutions and the return of the Papacy to conservative policies. As Piedmont was modernised, many liberals and other moderates began to support the idea of a Kingdom of North Italy. This even attracted some former Mazzinians.

A group was formed to press for a Kingdom of North Italy. Many former revolutionaries joined, for example: Manin (leader of the Venetian revolution in 1948/9) and Gioberti. These two largely came in due to the encouragement of Giorgio Pallavicino, a Lombard aristocrat, who financed newspapers and argued for national movement to rally round Piedmont. Some had argued for Murat (former King of Naples and brother-in-law of Napoleon I) as leader of a united Italy but in 1855 Manin decalred that Victor Emmanuel was the only possible King for Italy and that if he was in favour of unification then national movement would soon follow him.

In 1858 they attracted the support of Garibaldi. Now the National Society was created. Organised by Guiseppe La Farina, the aim of the Society was to set up committees all over Italy to promote leadership of Piedmont and its monarchy. It got off the ground to a much greater extent after the Plombieres agreement, when rumours of war with Austria were rife.

Contributions made by the National Society to the unification of Italy:

1. They co-operated with Cavour in stirring up a revolt in Massa and Carrara (the pretext for war).

2. They helped to arrange the transport of 20,000 volunteers to the war of 1859.

3. Their pro-Piedmont propaganda was intense through 1858/9. Rather than mention the revolution or even constitutionalism, the propaganda played up nationalism and the economic advantages of unification.

4. People linked to the National Society were those who founded and sustained the provisional governments in the Central Italian states (Parma, Modena, Tuscany and Romagna) in 1859/60.

5. They were insrumental in bringing about the decision of these duchies to ask for annexation by Piedmont. The main reason for this was the belief that only Piedmont could save them from outside intervention.