Austria (Anschluss) and October 1938: the annexation of the Sudetenland after the Munich Agreement March 1939: the German occupation of Czechoslovakia September/October 1939: the invasion of Poland April 1940: Operation Weserübung (the invasions of Denmark and Norway) May/June 1940: the Battle of France 1941: Operation Barbarossa and the Balkan Campaign. In all the occupied lands the Reichsbahn endeavoured to incorporate the captured railways (rolling stock and infrastructure) into their system. Even towards the end of the war the Reichsbahn continued to move military formations. For example, in the last great offensive, the Battle of the Bulge (from 16 December 1944), tank formations were transported from Hungary to the Ardennes. The railways managed by the "Eastern Railway Division" () were initially run from that part of the Polish State Railways within the so-called General Government-assigned part of the (PKP), but from November 1939 by the Ostbahn (Generalgouvernement). In the campaigns against Poland, Denmark, France, Yugoslavia, Greece etc. the newly acquired standard gauge networks could be used without difficulty. By contrast, after the start of the invasion of Russia on 22 June 1941, the problem arose of transferring troops and materiel to Soviet broad gauge lines or converting them to German standard gauge. Confounding German plans, the Red Army and Soviet railways managed to withdraw or destroy the majority of its rolling stock during its retreat. As a result, German standard gauge rolling stock had to be used for an additional logistic role within Russia; this required the laying of standard gauge track. The price was high: Reichsbahn railway staff and the railway troops of the Wehrmacht had to convert a total of of Soviet trackage to German standard gauge track between 22 June and 8 October 1941. During the war, locomotives in the war zones were sometimes given camouflage livery. In addition, locomotives were painted with the symbol (the eagle, Germany's traditional symbol of national sovereignty) holding a swastika. On goods wagons the name "" was replaced by the letters "DR". Postal coaches continued to bear the name "". The logistics of the were crucial to the conduct of Germany's military offensives. The preparations for the invasion of Russia saw the greatest troop deployment by rail in history. Expansion Characteristic of the first six and a half years of this period was the exponential growth of the , which was almost exclusively due to the takeover of other national railways. This