Lębork (; Kashubian/Pomeranian: Lãbórg) is a town on the Łeba and Okalica rivers in Middle Pomerania region, north-western Poland with some 37,000 inhabitants. Lębork is also the capital of Lębork County in Pomeranian Voivodship since 1999, previously in Słupsk Voivodship (1975-1998).
To gain an ally against Sweden during The Deluge, in 1657 King John II Casimir of Poland gave Lębork and Bytów to Margrave Frederick William of Brandenburg-Prussia as a hereditary fief in the Treaty of Bydgoszcz. Although Poland still retained sovereignty, Lębork was administered by Brandenburg and, after 1701, by the Kingdom of Prussia.
In 1773 after the First Partition of Poland, Polish sovereignty over Lębork was abandoned and the town was wholly incorporated in the Prussian Province of Pomerania. Lauenburg became part of the German Empire in 1871.
During World War II, Lauenburg was the location of the Nazi concentration camp Lauenburg, a subcamp of the Stutthof concentration camp. The town was ceded to Poland in 1945 and its German inhabitants were expelled and replaced with Poles.