1240 Izborsk and Pskov campaign

The Izborsk and Pskov campaign was a military conflict occurring in September 1240 in the Pskov Land. An alliance of the Bishopric of Dorpat, the Livonian Order (the former Livonian Brothers of the Sword, which had recently been incorporated into the Teutonic Order), and the pretender-prince Yaroslav Vladimirovich of Pskov besieged and conquered the Pskovian border fortress of Izborsk. After Pskovian defenders failed to retake the town, the allied forces advanced to the capital Pskov itself, compelling it to surrender.

The campaign resulted in the brief overthrow of the pro-Suzdalian faction that supported prince Aleksandr "Nevsky" Yaroslavich, and saw the installation of a new complex set of alliances. The situation ended after two years, when Nevsky led Novgorodian troops to retake Pskov under his family's control in spring 1242, and defeated the Dorpat–Livonian coalition at Lake Peipus.