The P38, developed by Carl Walther in 1938, had its early production for the German army marked with the Walther banner. In 1940, fearing Allied attacks, the banner was replaced with a secret code "480". This quickly changed to "ac". During the Nazi era, Walther produced 584,500 P38 pistols, marked with an inspection stamp (waffenamt) featuring an eagle over "359". In parallel, almost 30,000 HP (Heerespistole) were produced, which were basically a commercial version of the P38, some of these were delivered to the Swedish army and the German police.
Due to high demand, two more P38 manufacturers emerged in 1942: Mauser and Spreewerk. Mauser produced 323,000 pistols, initially marked "byf" and later changed to "svw" in early 1945. The factory was taken over by the French in April 1945, who continued production until 1946 for their own use, marking the pistols with "svw". Mauser's inspection stamp featured an eagle over "135" initially, changing to "E/WaA135" by late 1943.
Spreewerk, the 3rd manufacturer, began making P38 pistols in late 1942 using the code "cyq". They produced 283,080 pistols before Soviet conquest in April 1945. About 100 Soviet-supervised pistols (00-series) were made before production halted and the factory was disassembled. Spreekwerk's inspection stamp featured an eagle above "88" (E/88).