Sackheim was a quarter of eastern Königsberg, Germany. Its territory is now part of the Leningradsky District of Kaliningrad, Russia.
Although it was documented in 1326, Sackheim already existed as an Old Prussian farming village when the Teutonic Knights conquered Sambia in 1255 during the Prussian Crusade. The German name Sackheim was derived from the Prussian Sakkeim, meaning a village in cleared woodland. It was bordered by Löbenicht to the west, Neue Sorge to the north, Sackheim Gate and the early 17th century city walls to the east, and the Pregel River to the south. Beyond the walls was the road to Liep.
Few Germans lived in Sackheim during the Middle Ages; raftsmen from the Grand Duchy of Lithuania often stayed in the quarter, and much of Königsberg's Prussian Lithuanian population lived in Sackheim. It received a court seal and was made a Freiheit, or suburb subordinated to Königsberg Castle, in 1578. Sackheim's escutcheon depicted the Lamb of God with red standard on a green field.
Sackheim endured fires in 1513, 1539, and 1575. It was especially damaged by a city-wide conflagration on 11 November 1764.Altstadt, Löbenicht, Kneiphof, and their respective suburbs were merged to form the united city of Königsberg in 1724. However, Königsberg Castle and its suburbs, including Sackheim, were included within the new city limits but remained under royal, not municipal, control. Sackheim was merged into the city during the Städteordnung of Stein on 19 November 1808 during the era of Prussian reforms.