In the 15th century, shortly after the center of politics moved to Edo (now Tokyo), Shogun Tsunayoshi Tokugawa, who was born in the year of the dog and was also a dog lover, issued an order not to kill any animals or insects.

It was said that it was prohibited to eat pigs, chickens and seafood, so it would have been difficult for people who lived in such an era. One theory is that someone was punished for killing a mosquito, but it seems that the truth of this is not certain. However, 69 cases were punished and 13 people were sentenced to death just by actually confirming it.

There is a strong recognition among modern Japanese that it is a stupid decree by a stupid general of a dog lover. However, at that time, it was in an unsafe state of killing the vulnerable elderly and children meaninglessly, but it seems that such a situation has been greatly reduced by this decree. There is a story that the shogun originally intended to improve security by lamenting such a situation, so it may be a decree that should be highly evaluated.