Tortona

Tortona lies at the edge of the Po plain near routes across the Apennines toward Liguria. After a long siege, Frederick Barbarossa captured and destroyed the town in 1155. In 1347 Tortona came under the Visconti and thereafter followed the fortunes of the Milanese state.

Under Spanish rule in the early seventeenth century, the old castle and upper town were expanded into a fortress. The Treaty of Vienna in 1738 transferred Tortona from Milan to the House of Savoy, whose rulers rebuilt the fortifications in the 1770s. Its position on routes between the plain and the mountains continued to give it military and administrative importance.