Following the joint German-Soviet invasion of Poland, which started World War II in September 1939, Łanczyn was first occupied by the Soviet Union. In 1940 it became an urban-type settlement. From 1941 to 1944, it was occupied by Nazi Germany and administered within the District of Galicia. In 1944, it was re-occupied by the Soviet Union, and eventually annexed from Poland in 1945. In 1945–1947, expelled Poles from Lanchyn settled in the villages of Błażejów and Olszyny.[3]
Postwar, Lanchyn was briefly the center of the raion.
Until 26 January 2024, Lanchyn was designated urban-type settlement. On this day, a new law entered into force which abolished this status, and Lanchyn became a rural settlement.[4]
^Pawlikowska, Karolina (2016). "Rolnicze spółdzielnie produkcyjne powiatu kamiennogórskiego w latach 1950-1957, cz. 1 – organizacja i uwarunkowania działalności". Rocznik Jeleniogórski (in Polish). Vol. XLVIII. Jelenia Góra. p. 90. ISSN0080-3480.