The P38 was developed by Carl Walther in 1938. The first weapons produced for the German army were marked with the walther banner on the slide. In 1940 the walther banner was replaced by a secret code to indicate the manufacturer. The Germans were afraid that markings like the Walther banner would make it quit easy for the allies to determine the weapon production sites and bomb them. Therefore at the beginning of 1940 the pistols produced by the Walther plant were marked with the secret code 480 to indicate Walther as the manufacturer. This secret code was already replaced after two months with the new secret code ac. During the Nazi-regime 584.500 P38 pistols were produced by the Carl Walther plant in Zella Mehlis. Production was stopped when the American forces conquered the plant in April 1945. Weapons produced had to be inspected before they were delivered to the German Army. After approval the weapons were stamped with an inspection stamp (Waffenamt). The Walther inspection stamp consisted of an eagle above the number 359 (E/359).
The increasing demand of P38 pistols resulted in two more manufacturers in 1942, Mauser and Spreewerk. The mauser plant produced 323.000 P38 pistols during the nazi-regime and those pistols were stamped with the secret code byf to indicate mauser as the manufacturer. At the beginning of 1945 the secret code byf was replaced by the new secret code svw. The factory was conquered in april 1945 by the French. However the French did not stop production, they continued production of the P.38 for their own use until 1946. They also marked the pistols with the code svw. The initial Mauser inspection stamp consisted of an eagle above the number 135 (E/135) and changed at the end of 1943 to (E/WaA135).
Spreewerk was the thirth manufacturer who started producing P.38 pistols at the end of 1942. CYQ was used as secret code to indicate that the pistol was produced by the Spreewerk factory. Spreewerk produced 283.080 pistols before it was conquered by the Russians in April 1945. Around 100 pistols were produced under supervision of the Russians (00-series) before production was stopped and the factory dissambled. The Spreewerk inspection stamp consisted of an eagle above the number 88 (E/88).