Led by Gustavus Adolphus, the Swedish army advanced through Germany like a swarm of locusts, leaving a devastated countryside in their wake. Their opposition, the Catholic League and the Habsburg Imperial Army did their best to offer resistance.
The two sides met on 7th September 1631 on an open field near the village of Breitenfeld, outside Leipzig and the ensuing battle became the biggest of the Thirty Years War. Gustavus Adolphus and the Swedish army, with Saxon reinforcements, faced the Imperial army under the command of General Tilly. The Swedes went into battle under the war cry “Gott mit uns”, in English “God with us”. (this motto would subsequently be used by the Prussian army and later by German forces during WWI & the Wehrmacht during WW2, when the motto was embossed on the soldiers’ belt buckles).
After seven hours of battle, the Swedish-Saxon army were victorious, thanks to their exceptional discipline, great mobility and superior firepower. Twelve thousand men lay dead on the battlefield.
The victory at Breitenfeld was the height of Gustavus Adolphus’ military career but his victory march continued. Nuremberg, Frankfurt am Main and Munich were conquered. He gained a reputation for being undefeatable but did not live long enough to realise his dream of becoming Holy Roman Emperor. The following year, on 6th November 1632, he fell in battle outside the city of Lützen in eastern Germany but the war continued.