False Dmitriy
Russia under the new tsar Vasili Shuysky remained unstable. A new false Dmitriy materialized and Tsaritsa Marina had even "recognized" in him her thought-to-be-dead husband. With a new army provided largely by the magnates of the Commonwealth, False Dmitriy II approached Moscow and made futile attempts to take the city. Tsar Vasili IV, seeking help from King Charles IX of Sweden, agreed to territorial concessions in Sweden's favor and in 1609 the Russo-Swedish anti-Dmitriy and anti-Commonwealth alliance was able to remove the threat from Moscow and strengthen Vasili. The alliance and the Swedish involvement in Russian affairs caused a direct military intervention on the part of the Polish–Lithuanian Commonwealth, instigated and led by King Sigismund III, with the support of the Roman Curia.