Cryptographic letter of Peter I

The letter (see Fig. 1), personally encrypted by Peter I, was probably sent to Prince V. V. Dolgorukov , who at that time suppressed the Bulavin uprising on the Don . Excessive cruelty, comparable only to the massacre of rebel archers , is due to the fact that the Swedes again stood at the borders of Russia , ready to invade its borders and had to rebel "to exterminate themselves from such gaze free in this war."

A significant part of the letter is “claire” - unencrypted words and sentences . This was done in the interest of facilitating the encryption process.

From the modern point of view, this is a simple replacement cipher , where the letters of the plain text are replaced by special characters and Arabic numerals (see Fig. 3), which at the beginning of the 18th century were introduced instead of the outdated Cyrillic alphabetical numbering.

Due to the fact that some characters are similar in style, there are a lot of descriptions in the encrypted part of the letter ^[1] (see Fig. 2). So instead of the sign of the letter B, the sign of the letter T is written (and vice versa) on the 3rd line , on the 8th line twice and on the 10th. Instead of the sign of the letter Y, the sign of the letter B is written on the 3rd line and on the 8th. The lack of the sign of the letter G (in the form of the Latin letter Z) on the 6th line led to the fact that it became the sign of the letter P (in the form of the number 7) On the 8th line in the encrypted word, the letter X was not encrypted and became the sign of the letter D . Along with clerical errors, there are obvious encryption errors. So on the 11th line, instead of the sign of the letter D, the sign of the letter B is written. On the 12th line, the letter E must be written in capital Latin h. Instead, the capital Latin H is written. On the 13th line, instead of the letter D, the letter T is written.

Errors and clerical errors, although confusing, do not violate the general course of thought.

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  Fig. 2

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  Fig. 3