Nowadays, this phrase is perceived as a fun linguistic game that illustrates the importance of punctuation marks. However, its origin is much more serious - it is believed that it is associated with actual executions initiated by royal persons.
The exact origin of the phrase is still unknown; over the past two or three centuries, they have become accustomed to associating it with Russian tsars from Peter I to Alexander III. The American journalist Robert Ripley even wrote an article about the latter in his newspaper: the tsar drew up a sentence to certain state criminals, prescribing exile to Siberia, but the empress changed the point, thanks to which the accused were pardoned.
There is also a legend according to which the Queen of England Isabella wrote a similar phrase in a letter to the jailers who guarded the convicted King Edward II. The queen hesitated with the verdict: if the king is left alive, then his supporters can revolt and again elevate him to the throne; if executed, it could undermine the authority of royal power in general.
Therefore, Isabella deliberately drew up an ambiguous order in order to blame the jailers for everything and say that she, they say, meant something completely different. Edward, of course, was killed, and his death was passed off as natural. But this did not help them: Edward's son, having occupied the throne, identified and executed his father's killers. According to another version, the king was executed in the most obvious and shameless way, by driving a red-hot poker into his anus.