Early in the eighteenth century, the Italian states were involved in a series of territorial wars, and the various states passed under Spanish, French, and Austrian control. But by 1748, political affairs were comparatively settled, and remained so until the French Revolution: Austrian Habsburg control of much of the north, Bourbon control of Naples, Savoy control of Sardinia, and papal control of the Papal States.
Italy, like all of Europe, was influenced by the new ideas about society, theology, and statecraft circulating during the eighteenth century. Italian intellectuals -- including Giambattista Vico, Gian Vincenzo Gravina, Pietro Varri, Cesare Beccaria, Pietro Verri (especially in Il caffè), and Ludovico Antonio Muratori -- produced important critiques of contemporary society, many directed at the papacy's abuses of power and the relationship between church and state. The response from those in power was much friendlier than in reactionary ancien régime France. The Italian governments (especially Maria Theresa in the 1740s and Joseph II in the 1770s) made various attempts to modernize the financial and agricultural systems of their states, but to small effect.
But eighteenth-century Italy never had the sort of crisis experienced in France, for before before domestic affairs came to a head, Italy was placed under French rule. Savoy and Nice were the first to fall, beginning in 1792. Between March 1796 and 1799, Napoleon's forces overran the entire Italian peninsula, and French-controlled governments were installed. Only Sicily and Sardinia remained beyond the French sphere of influence.
The French were welcomed by many Italian intellectuals, known as patrioti, who formed secret radical societies modeled after the Bavarian Illuminati. But French rule was never genuinely popular in Italy, and it was certainly not favored by the displaced ruling classes. There were many uprisings against Napoleon and the Jacobins who supported him, and over time even many of the former supporters of the French formed anti-Jacobin societies with a strong nationalist bent.
Between the first invasions in 1796 and 1814, all the important Italian leaders had been replaced -- in 1809, in fact, even the Pope's temporal powers were suspended and the Pope himself imprisoned. Napoleon, in the hopes of turning Italy into a group of "sister republics," began reorganizing the country on French principles. The most significant changes came in the north, where an invasion from Austria was a threat to Napoleon's forces. Parts of northern Italy, including most of Lombardy and Emilia-Romagna, were reorganized, first as the Cisalpine Republic, then as the Italian Republic, and finally in 1805 as the Kingdom of Italy, with Napoleon as king. Piedmont, Genoa, Parma, Tuscany, and the Papal States were incorporated into France, while Naples was ruled by Napoleon's brother, Joseph, from 1805 to 1808, and later by his brother-in-law.
After the collapse of Napoleon's military fortunes in 1815, the Congress of Vienna freed Italy from French domination. In the Restoration, the three states established by the French were dissolved, French laws were systematically abolished, and the most of the traditional states were restored. The country did not, however, return entirely to the status quo ante: Austria, for instance, gained control over Trento and the new Kingdom of Lombardy-Venetia, and remained powerful throughout Italy. And many of the judicial reforms under Napoleon remained in force.
There were inevitably calls for further liberalization in the years after the Restoration, especially from members of a secret society known as I Carbonari. The nationalist and anti-Austrian Carbonari called for greater rights of the bourgeoisie, and joined in a march on Naples in 1820. The rebellion was quickly quashed with the help of Austrian forces. But a similar rebellion occurred shortly afterwards in Piedmont, and organized resistance to the old-style government was growing throughout the Italian states. Bad harvests contributed to popular unrest throughout the 1820s, and the French July Revolution of 1830 served as a spark to touch off a series of (ultimately unsuccessful) republican nationalist rebellions, organized by Giuseppe Mazzini and Giuseppe Garibaldi. Only an economic upturn coupled with reactionary and oppressive government policies succeeded in bringing peace.
The nationalists and republicans were silenced only temporarily. When the unpopular Austrians occupied Ferrara in the Papal States in 1847, they prompted a widespread series of insurrections beginning in Palermo in January 1848. By March, Austria had lost most of its Italian territory. In February 1849, a democratic assembly proclaimed the Roman Republic in the former Papal States. The liberal gains were short-lived -- Austria regained control of most of northern Italy, and Louis-Napleon invaded in 1850 and restored the papacy. But the great nationalist effort known as the Risorgimento was not defeated. Under the leadership of Giuseppe Garibaldi, in a series of battles beginning in 1859, Italian nationalist leaders were able to drive the Austrian occupiers from Italy and united many of the smaller states. The Kingdom of Italy was proclaimed in 1861; Venetia was annexed after the Austro-Prussian war in 1866; and Rome was taken from the Pope in 1870.