Rethem is a town located in the Heidekreis district of Lower Saxony, Germany. It is situated along the river Aller, positioned approximately 18 kilometers southeast of Verden and about 25 kilometers southwest of Bad Fallingbostel.
The town was historically significant as a site of intense military conflict during World War II. Between April 10 and April 11, 1945, heavy fighting occurred in the area involving units from the British 53rd Welsh Division and parts of the German 2. Marine-Infanterie-Division. The engagement resulted in heavy losses on both sides, with many of the German soldiers involved being under the age of 23.