The complete end of belligerent occupation

Treaty of peace

645. Belligerent occupation goes on as long as the Occupying Power continues to exercise effective control in an occupied territory, and the war (which may manifest itself exclusively in the ongoing occupation) is not over. Normally, the end of the occupation and of the war will coincide and occur following the conclusion of a treaty of peace. The displaced sovereign will then retrieve possession of the occupied territory and restore its control there. However, it is possible that the treaty of peace (or a related agreement) will allow – for a period of time – the uninterrupted presence of foreign troops in the formerly occupied territory, notwithstanding the reversion of the area to the restored sovereign (see the example of the Rhineland supra 82).

646. The treaty of peace may even permit future return of armed forces of the (formerly) Occupying Power to at least a portion of what used to be an occupied territory, in response to a material breach of its provisions by the restored sovereign. Article 430 of the Treaty of Versailles permitted such reoccupation as a countermeasure against Germany's possible failure to observe its obligations in the sphere of reparations. In the event, France and Belgium actually reoccupied the Ruhr Valley on that basis in 1923. Since the renewed occupation in such circumstances is implanted in an agreement (the treaty of peace), it cannot be regarded as belligerent in nature (see supra 79).