Tangermünde (taŋɐˈmʏndə; Tangermünn) is a historic town on the Elbe River in the district of Stendal, in the northeastern part of Saxony-Anhalt, Germany.
Tangermünde is situated in the historic Altmark region of the North German Plain, on a glacial terminal moraine, above the left shore of the Elbe. The town's name derives from the mouth (Mündung) of the Tanger tributary. The altitude protects it from floods.
Since the administrative restructuring effective January 1, 2010, the area of Tangermünde comprises the former municipalities of Bölsdorf, Buch, Grobleben, Hämerten, Langensalzwedel, Miltern, and Storkau. These former municipalities are now Ortschaften (divisions) of the town Tangermünde.
Tangermünde can look back at a thousand-year-long history as already in 1009 the medieval chronicler Bishop Thietmar of Merseburg referred to a local lowland castle, which probably had been erected in the early 10th century during the rule of King Henry the Fowler at the border with the lands of the Polabian Slavs incorporated into the Saxon Marca Geronis.
The town itself was first mentioned in a 1275 deed, governed by a succession of vogts (reeves), such as Ruthger von Blumenthal. Due to its favourable location, it soon became a point where tolls were charged on boats sailing along the Elbe River as well as a residence of the Ascanian margraves of Brandenburg. Margrave John II hid his treasure under the parish church, and passed the secret to his brother Otto with the arrow. When the latter was held to ransom by the citizens of Magdeburg in 1278, he used the treasure to pay for his release.
Upon the extinction of the Ascanian dynasty, the town was one of the favourite places of the Luxembourg emperor Charles IV, who had purchased the Margraviate of Brandenburg in 1373 and had Tangermünde Castle (German: Burg Tangermünde) rebuilt as a Kaiserpfalz, including a chapter of Canons Regular. From 1415 onwards, it became the residence of the Hohenzollern electors, after the Nuremberg burgrave Frederick VI was enfeoffed with Brandenburg by Charles' son Emperor Sigismund.