information:extraction, structural:scholar_edition, stylistic:style_transfer, information:classification, structural:summarization
Aspirations of Livonia's neighbours

By the time the Livonian War broke out, the Hanseatic League had already lost its monopoly on the profitable and prosperous Baltic Sea trade. While still involved and with increasing sales, it now shared the market with European mercenary fleets, most notably from the Dutch Seventeen Provinces and France. The Hanseatic vessels were no match for contemporary warships, and since the league was unable to maintain a large navy because of a declining share of trade, its Livonian members Riga, Reval (Tallinn), and trading partner Narva were left without suitable protection. The Danish navy, the most powerful in the Baltic Sea, controlled the entrance to the Baltic Sea, collected requisite tolls, and held the strategically important Baltic Sea islands of Bornholm and Gotland.

A long bar of Danish territories in the south and lack of sufficient year-round ice-free ports severely limited Sweden 's access to Baltic trade. Nevertheless, the country prospered due to exports of timber, iron, and most notably copper, coupled with the advantages of a growing navy and proximity to the Livonian ports across the narrow Gulf of Finland. Before the Livonian War, Sweden had sought expansion into Livonia, but the intervention of the Russian tsar temporarily stalled these efforts through the Russo-Swedish War of 1554–1557, which culminated in the 1557 Treaty of Novgorod.

Through its absorption of the principalities of Novgorod (1478) and Pskov (1510), the Tsardom of Russia had become Livonia's eastern neighbour and grown stronger after annexing the khanates of Kazan (1552) and Astrakhan (1556). The conflict between Russia and the Western powers was exacerbated by Russia's isolation from sea trade. The new Ivangorod port – built in 1550 during the reign of Tsar Ivan IV on the eastern shore of the Narva River – was considered unsatisfactory on account of its shallow waters. Thereafter the tsar demanded that the Livonian Confederation pay about 6,000 marks to keep the Bishopric of Dorpat, based on the claim that every adult male had paid Pskov one mark when it had been an independent state. The Livonians eventually promised to pay this sum to Ivan by 1557, but were sent from Moscow when they failed to do so, ending negotiations. Ivan continued to point out that the existence of the Order required passive Russian support, and was quick to threaten use of military force if necessary. He aimed to establish a corridor between the Baltic and the new territories on the Caspian Sea, because if Russia were to engage in open conflict with major western powers, it would need imports of more sophisticated weaponry.

The Polish King and Lithuanian Grand Duke Sigismund II Augustus was wary of Russian expansionist aspirations. Expansion of Russia into Livonia would have meant not only a stronger political rival but also loss of lucrative trade routes. Therefore, Sigismund supported his cousin Wilhelm von Brandenburg, archbishop of Riga, in his conflicts with Wilhelm von Fürstenberg, the Livonian Order's landmeister. Sigismund hoped that Livonia, just like the Duchy of Prussia under Duke Albert, would become a vassal state of Poland–Lithuania. With weak support in Livonia, von Brandenburg had to largely rely on external allies. Among his few Livonian supporters was landmarschall Jasper von Munster, with whom he planned an April 1556 attack on his opponents that would involve military aid from both Sigismund and Albert. However, Sigismund hesitated over participation in the action, fearing that it would leave the Kiev Voivodeship exposed to a pending Russian attack. When von Fürstenberg learned of the plan, he led a force into the archbishopric of Riga and in June 1556 captured the main strongholds of Kokenhusen and Ronneburg. Jasper von Munster fled to Lithuania, but von Brandenburg and Christoph von Mecklenburg were captured and detained at Adsel and Treiden. This resulted in a diplomatic mission to petition for their release being dispatched by the Pomeranian dukes, the Danish King, Emperor Ferdinand I, and the estates of the Holy Roman Empire. A cross-party meeting in Lübeck to resolve the conflict was scheduled for 1 April 1557, but was cancelled due to quarrels between Sigismund and the Danish envoys. Sigismund used the killing of his envoy Lancki by the landmeister's son as an excuse to invade the southern portion of Livonia with an army of around 80,000. He forced the competing parties in Livonia to reconcile at his camp in Pozvol in September 1557. There they signed the Treaty of Pozvol, which created a mutual defensive and offensive alliance, with its primary target Russia, and provoked the Livonian War.