July 6, 1630

Gustavus Adolphus lands on Usedom and brings Sweden into the war

On 6 July 1630 (26 June Old Style) Gustavus Adolphus lands his army on Usedom, off Pomerania, and Sweden enters the war. Sources differ on the force, from about 4,000 to 13,000 men. He occupies Pomerania under the Treaty of Stettin.