Neutralized Zone of Savoy
The Neutralized Zone of Savoy was a zone of neutrality to the north of the Duchy of Savoy (corresponding more or less to the provinces of Faucigny and Chablais Savoyard, part of Genevois and Savoy proper), part of the States of Savoy or the Kingdom of Sardinia. It was set up under the treaties that followed the two abdications of the French Emperor Napoleon I in 1815.
Source: Wikipedia — Neutralized Zone of Savoy (CC BY-SA 4.0)