Cisalpine Republic (sĭsăl`pīn), Italian state created by Napoleon Bonaparte in 1797 by uniting the Transpadane and Cispadane republics, which he had established (1796) N and S of the Po River. The new republic included the former duchies of Milan, Parma, and Modena, the legations of Bologna and Ferrara, and the Romagna. By the Treaty of Campo Formio (1797), Austria recognized the republic, to which were added the Venetian territories W of the Adige (including Bergamo and Brescia), the duchy of Mantua, and the formerly Swiss Valtellina. The republic was in fact subject to France, and its constitution was based on the French model. In 1799 the Austro-Russian armies occupied it, but Bonaparte recovered it in 1800. By the Treaty of Lunéville (1801) its nominal autonomy was restored. In 1802 it became the Italian Republic and in 1805, with the addition of Venetia, the Napoleonic kingdom of Italy. It was broken up by the Congress of Vienna Vienna, Congress of, Sept., 1814–June, 1815, one of the most important international conferences in European history, called to remake Europe after the downfall of Napoleon I.
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Cisalpine Republic

Former republic, northern Italy. Created by Napoleon in 1797 from conquered territories, it was centred in the Po River valley and included the lands around Milan and Bologna. It was incorporated into the Napoleonic kingdom of Italy in 1805.