In 1939, during the invasion of Poland at the very beginning of World War II, the major Battle of Tuchola Forest was fought in the area. Soon, the former military test area was occupied again by German troops, and called "Truppenübungsplatz Westpreußen", or by its code name, "Heidekraut". During the occupation, in October and November 1939, Germans murdered 335 Poles from Tuchola and Tuchola County in six large massacres in Rudzki Most. Among the victims were teachers, school principals, merchants, craftsmen, farmers, priests, foresters, postmen, railwaymen, policemen and local officials, including mayor of Tuchola Stanisław Saganowski.