The regiment was raised around 1624 during the Polish–Swedish War of 1621–25, originally recruited from Swedish provinces. Following the landing of Gustavus Adolphus and his army in Pomerania, new recruits came from local German inhabitants to fill the ranks. From 1630 onward, the Blue regiment took part in almost every battle of the Swedish intervention in the Thirty Years' War, such as the battle of Breitenfeld (1631), Lützen (1632) and Nördlingen (1634). Battle of Lützen in particular, where it is referred to as the "Old Blue" regiment, though this name was official from 1634 only, was disastrous to the regiment as it lost more than half of its veteran soldiers from the recurring attacks of the Imperial cavalry and the heavy enemy volleys.