During the last year of the war, the concentration camp prisoner population reached its peak. The SS deployed hundreds of thousands of prisoners on war-related forced labor projects, including some of the most important to the war effort. In the meantime, many war factories had been bombed by the Allies, leading to the decision to disperse production. In 1943, the Auto Union factory in Chemnitz-Siegmar was ordered to be turned over to the production of Maybach HL230 tank engines, much in demand due to attrition on the Eastern Front. By late 1943, Hermann Göring (head of the Four Year Plan for war production, which involved mass forced labor) was planning to disperse the Maybach production from the Chemnitz plant to an underground factory under Radobýl Mountain just west of the town of Leitmeritz (now Litoměřice in the Czech Republic). Although there was an existing quarry, the facility had to be expanded in order to accommodate planned spaces for production and assembly several kilometers long. The site was located in Reichsgau Sudetenland, a territory of Czechoslovakia that had been annexed to Germany in 1938 following the Munich Agreement.