The Cisalpine Republic (Repubblica Cisalpina; Emilian-Romagnol: Repóblica Ciṣalpèina; Republica Cisalpina) was a sister republic of France in Northern Italy that existed from 1797 to 1799, with a second version until 1802.
After the Battle of Lodi in May 1796, Napoleon Bonaparte organized two states: one to the south of the Po, the Cispadane Republic, and one to the north, the Transpadane Republic. On 19 May 1797, Napoleon transferred the territories of the former Duchy of Modena to Transpadania and, on 12 Messidor (29 June), he decreed the birth of the Cisalpine Republic, creating a Directory for the republic and appointing its ministers. France published the constitution of the new republic on 20 Messidor (7 July), establishing the division of the territory into eleven departments: Adda (Lodi), Alpi Apuane (Massa), Crostolo (Reggio), Lario (Como), Montagna (Lecco), Olona (Milan), Panaro (Modena), Po (Cremona), Serio (Bergamo), Ticino (Pavia), and Verbano (Varese).
The rest of Cispadania was merged into the Cisalpine Republic on 27 July, with the capital of the unified state being Milan. On 1 Brumaire (22 October), Bonaparte announced the union of Valtelline with the Republic, after its secession from the Swiss Three Grey Leagues. Austria acknowledged the new entity in the Treaty of Campoformio of 17 October, gaining in exchange what remained of the Venetian Republic. On 25 Brumaire (15 November), the full international recognition and legality of the new state was ratified by the law governing the final annexation of the conquered territories.
The parliament, composed of two chambers (the Great Council and the Council of the Seniors), was appointed directly by Napoleon on 1 Frimaire (21 November). He justified this undemocratic action as a necessity of war. New departments joined the eleven original ones and Valtelline in the following months: Benaco (Desenzano) on 11 Ventose (1 March 1798), Mella (Brescia) on 13 Floreal (2 May), Mincio (Mantua) on 7 Prairial (26 May), and five departments of Emilia.