
During the Great Patriotic War, letters were the main method of communication between the military and the civilian population. And, of course, when it comes to field mail, we remember the famous yellowed sheets folded in triangles. But not everyone knows why the letters from the front were without envelopes and folded in such an unusual shape.
Postal communication in the USSR was established literally from the first days of the war. The General Directorate of Communications of the Red Army established the creation of the Office of the Military Field Mail, which consisted of the Postal Field Stations, or PPS, operating directly in the units. After a while, they were changed to Military Post Stations (UPU).
Interesting fact: the changes even affected the appearance of the stamp: with the PPS, the current number of the field station was not indicated on it, while the UPU stamp already had this information.

Such a prompt creation of postal communications at the front is due to both practical needs and great popularity: according to Novate.ru, the volume of monthly letters sent through Field Stations was approximately seventy million units. In addition to establishing the system itself, postal services have gained maximum availability - from the day of the attack of the Third Reich, sending letters became free, and stamps were also canceled as mandatory for messages to the front and rear.

However, quite soon the problem of the presence of the envelopes themselves arose. Considering the huge volumes of letters, they simply did not have time to produce them in the required quantity. In addition, paper mills simply lacked raw materials.
It was in these conditions that the legendary folk manifested itself in time. According to researchers and even to the personal testimony of Marshal Zhukov, it was the soldiers of the Red Army who found a way out of this situation. At first, they made envelopes from newspapers with their own hands, and when they ceased to suffice, they simply began to fold their letters into triangles.

By the way, the disappearance of envelopes from field mail is also associated with a shortage of paper, even for the records themselves. Sometimes soldiers had to write to their relatives and friends literally on the remains, scraps of paper. At the same time, such messages had room for the recipient's address and sender's data, so there was simply no need for envelopes.

Apart from the disappearance of the envelopes, there was absolutely no confidentiality in the field soil. The triangle letters were not glued. Yes, it was simply a useless waste of time: they were still revealed by the "special officers" of the NKVD. It is believed that it was for this reason that the letters of the German soldiers were much more informative and voluminous than those of the Red Army. Moreover, the messages were checked from both sides: each triangle from a soldier or from a member of his family necessarily had the stamp “Checked by military censorship”.

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