Gustavus Adolphus inherited three wars from his father when he ascended the throne: against
Denmark–Norway, which had attacked Sweden earlier in 1611; against Russia, due to Sweden having tried to take advantage of the Russian
Time of Troubles; and against
Poland-Lithuania, due to King Charles's having deposed King Sigismund III, his nephew, as King of Sweden. The war against Denmark–Norway (
Kalmar War), during which Gustavus Adolphus fought in minor military actions, — the victorious for Sweden
Storming of Kristianopel and the unsuccessful
Battle of Vittsjö, — was concluded in 1613 with a peace that did not cost Sweden any territory except for Älvsborg Castle, which Sweden had to
pay to get back, but it was forced to pay a heavy indemnity to Denmark–Norway (
Treaty of Knäred). During this war, Gustavus Adolphus let his soldiers plunder towns and villages, and as he met little resistance from Danish forces in
Scania, they pillaged and devastated twenty-four Scanian parishes. His reputation in
Scania has been negative because of these actions. The largest destroyed settlement was the town
Væ. The war against Russia (
Ingrian War) marked Gustavus Adolphus's involvement in the successful
Siege of Gdov and the failed
Siege of Pskov and ended in 1617 with the
Treaty of Stolbovo, which excluded Russia from the Baltic Sea. The final inherited war, the
war against Poland, ended in 1629 with the
Truce of Altmark, which transferred the large province of
Livonia to Sweden and freed the Swedish forces for the subsequent intervention in the
Thirty Years' War in Germany, where Swedish forces had
already established a bridgehead in 1628. In a round of this dynastic dispute, Gustavus Adolphus invaded Livonia when he was , beginning the Polish-Swedish War. In the course of it he won a
victory at Wallhof, fought at
Gniew,
Dirschau, and suffered a
defeat at Trzciana. In April 1627, he was made a knight of the
Order of the Garter by King
Charles I of England.
Thirty Years' War in 1631 The electorate of
Brandenburg was especially torn apart by a quarrel between the Protestant and Catholic parties. The Brandenburg minister and diplomat baron influenced Gustavus Adolphus to support and protect the Protestant side in Germany. As a result of these negotiations, Gustavus Adolphus launched an invasion of northern Germany and
Pomerania in June 1630, marking the
Swedish intervention in the Thirty Years' War. He had just 4,000 troops. He was soon able to consolidate the
Protestant position in the north, however, using reinforcements from Sweden and money supplied by France at the
Treaty of Bärwalde. Gustavus Adolphus intervened on the anti-Imperial side, which at the time was losing to the Holy Roman Empire and its Catholic allies; the Swedish forces would quickly reverse that situation. His occupation of Pomerania was carried out according to the
Treaty of Stettin (1630). On 25 December 1630, he led
an assault on Greifenhagen, resulting in the capture of the city. After Swedish plundering in Brandenburg (1631) endangered the system of retrieving
war contributions from occupied territories, "marauding and plundering" by Swedish soldiers was prohibited. At Breitenfield, Gustavus Adolphus led a larger force against the Imperialist army and made use of a combined attack of cavalry, well-disciplined infantry and the effect of the more numerous and more mobile Swedish artillery to break the Imperial lines. Tilly's forces were entrenched on the eastern bank of the river. At Alte Veste, Gustavus Adolphus led some 56,000 troops to battle against some 70,000 Imperial and Bavarian troops but was defeated and forced to withdraw northwards. Gustavus Adolphus would suffer the effects of the wounds for the rest of his life. Among the minor effects were on his handwriting. His artillery were themselves different—in addition to the usual complements of heavy cannon, he introduced light mobile guns for the first time into the Renaissance battlefield. These were grouped in batteries supporting his more linearly deployed formations, replacing the cumbersome and unmaneuverable traditional deep squares (such as the Spanish
tercios that were up to 50 ranks deep) used in other pike and shot armies of the day. In consequence, his forces could redeploy and reconfigure very rapidly, confounding his enemies. On 30 June 1632, Gustavus Adolphus signed the decree for the foundation of Academia Dorpatensis in Estonia, today known as the
University of Tartu. Despite significant hardships for the common people, the period of Swedish rule over Estonia has been idealized in local folklore as the "good old Swedish times", which has been attributed to comparisons with the harder times that followed under the Russian rule. On 27 August 1617, his speech before his
coronation included the following statement: I had carefully learned to understand, about that experience which I could have upon things of rule, how fortune is failing or great, subject to such rule in common, so that otherwise I would have had scant reason to desire such a rule, had I not found myself obliged to it through God's bidding and nature. Now it was of my acquaintance, that inasmuch as God had let me be born a prince, such as I then am born, then my good and my destruction were knotted into one with the common good; for every reason then, it was now my promise that I should take great pains about their well-being and good governance and management, and thereabout bear close concern. ==Death and aftermath==