The Siege of Pskov took place during the final stage of a war that fought for control of what area?
Livonian War The Livonian War (1558–1583) was fought for control of Old Livonia (in the territory of present-day Estonia and Latvia), when the Tsardom of Russia faced a varying coalition of Denmark–Norway, the Kingdom of Sweden, and the Union (later Commonwealth) of the Grand Duchy of Lithuania and the Kingdom of Poland.
Zaporizhian Sich The Zaporozhian Sich (, "Zaporoz'ka Sich"; Polish: "Sicz Zaporoska" ; Russian: Запорожская Сечь ) was a semi-autonomous polity of Cossacks in the 16th to 18th centuries, centred in the region around today's Kakhovka Reservoir spanning the lower Dnieper river in Ukraine. In different periods the area came under the sovereignty of the Polish-Lithuanian Commonwealth, the Ottoman Empire, the Tsardom of Russia, and the Russian Empire. In 1775, shortly after Russia annexed the territories ceded to it by the Ottoman Empire under the Treaty of Küçük Kaynarca (1774), Catherine the Great disbanded the Sich and incorporated its territory into the Russian province of Novorossiya.