Tilly fought the Danes at the Battle of Lutter on 26–27 August 1626, in which his highly disciplined infantry charged the enemy lines four times, breaking through. This led him to win decisively, destroying more than half the fleeing Danish army, which was uncharacteristic of the warfare of the time. Denmark was forced to sue for peace at the Treaty of Lübeck. This disrupted the balance of power in Europe resulting in Swedish involvement in 1630 under their redoubtable leader, the brilliant King and field general Gustavus Adolphus of Sweden, who had been trying to dominate the Baltic for the previous ten years in wars with Poland, then a continental power of note.