For most of its history, the Italian peninsula has not been unified as the one country. In ancient times, the area was settled by a variety of civilisations, including the Etruscans in Tuscany and the Greeks in the south, before the peninsula was united under the Roman Republic and Roman Empire. Italy was once again divided in the Middle Ages, with the north divided between a series of powerful city-states – including Florence, Venice, and Siena – while the south came under the rule of successive empires, including the Holy Roman Empire and the Spanish Empire. While Northern Italy’s city states were at the forefront of trade and economics during the Renaissance, by the 18th century, the Italian peninsula was in economic and political decline. In the very early 19th century saw the peninsula briefly united under the rule of the French Emperor Napoleon Bonaparte. This moment inspired the emergence of a nationalist movement, shaped by Romanticism and the republicanism of the French Revolution. In 1858, the Kingdom of Sardinia (despite the name, concentrated in the prosperous northern Italian region of Piedmont) signed a treaty with Napoleon III guaranteeing French aid in the case of Austrian aggression in the Italian Peninsula, in exchange for parts of Savoy and Nice. The Franco-Austrian War of 1859-61 saw the incorporation of Lombardy into Sardinia, and the retreat of Austria into the east. At the same time, the revolutionary Giuseppe Garibaldi invaded Sicily and Southern Italy in the name of the King of Sardinia with a corps of volunteers. Joined by locals, they succeeded in claiming Southern Italy in 1860. In 1861, Sardinia took parts of central Italy, and proclaimed the creation of a single Italian state that year. Over the following nine years, Tuscany, the Veneto, and Rome were all incorporated into the Italian Kingdom. Unity was complete, and a parliament was established in Rome in 1871. Even today, however, deep cultural differences remain between the different regions of Italy.