Transalpine campaigns of the Old Swiss Confederacy

The transalpine campaigns of the Old Swiss Confederacy, known as Ennetbirgische Feldzüge "transmontane campaigns" in Swiss historiography, were military expeditions which resulted in the conquest of territories south of the Alps, corresponding more or less to the modern canton of Ticino, on the part of the Old Swiss Confederacy. These territories were known as ennetbirgische Vogteien or "transmontane bailiwicks".

The Leventina was the first transalpine possession of the Swiss cantons of Uri and Obwalden, acquired in 1403. Other territories were acquired in 1418 and 1419. A first setback came with the Battle of Arbedo in 1422, where the Swiss were defeated by the Duchy of Milan, and in a treaty of 1426, the border of the duchy was moved back to the Gotthard Pass. Renewed campaigns took place in 1439, 1441 and 1447, until in 1449 the Swiss were beaten again by troops of the Golden Ambrosian Republic in the Battle of Castione.

In 1466, the duke of Milan promised to grant the Leventina to the confederates, but he was slow to act on his promise, and as the Swiss were tied up in the Burgundian Wars he even formed a pact with the Burgundians. This prompted Uri to send an expedition to the Leventina, which was greeted as liberators by the local population. The Swiss tried to conquer Bellinzona as well, but after a two weeks' siege gave up and returned home. The Battle of Giornico was for once a Swiss victory, in which a force of Uri of about 175 men, with the support of about 400 men from the local population, managed to rout a Milanese army of 10,000. From this time, the Leventina was an undisputed possession of Uri, while Bellinzona remained under Milanese control.

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