Battle of Frankfurt an der Oder

Date	13 April 1631
Location	Frankfurt an der Oder (present-day Germany)
Result	Swedish victory

Belligerents

Commanders and leaders

Casualties and losses

800 killed or wounded

3,000 killed or wounded

The Battle of Frankfurt an der Oder on 13/15 April 1631 was a battle of the Thirty Years' War, fought between the Swedish Empire and the Holy Roman Empire for the strategically important, fortified Oder crossing Frankfurt an der Oder, Brandenburg, Germany. The town was the first major Imperial stronghold attacked by Sweden outside the Duchy of Pomerania, where Sweden had established a bridgehead in 1630. After a two-day siege, Swedish forces, supported by Scottish auxiliaries, stormed the town. The result was a Swedish victory. With the subsequent clearance of nearby Landsberg (Warthe) (now Gorzow), Frankfurt served to protect the Swedish army's rear when Gustavus Adolphus of Sweden proceeded further into Central Germany.

Swedish king Gustavus Adolphus started to intervene in the Thirty Years' War by supporting Stralsund against Wallenstein in 1628, and landed in Pomerania in June 1630. With the central parts of the Duchy of Pomerania, Sweden had gained a bridgehead in the Holy Roman Empire's northeasternmost corner, while the rest of the empire was occupied by forces of the Catholic League and Ferdinand II, Holy Roman Emperor. Except for Magdeburg, which had allied with Sweden on 1 August, the German Protestant states distrusted Gustavus Adolphus and hesitated to enter an alliance.