Chiusi is a town full of history and culture as well as an important archeological centre at an international level. It has Umbro-etruscan origins. It experienced a period of great expansion between the VII and V centuries BC; afterwards, it was under the Roman influence. As seat of the Longobard Dukedom in 1765, it experienced a decay caused by marshland and the consequent malaria. It was first under the influence of Orvieto and then Siena; for a short period it became a free city before being surrendered again to Siena and , as a result, being a part of the Dukedom of Florence.