Why set off firecrackers in the countryside on the fourth day of July?

Setting off firecrackers on July 4th is a custom to exorcise evil spirits. Specifically, it may be related to the following two reasons:

1. It is said that the gate of hell is closed at the first day of July and at the fourth day of July. People are afraid of being shut down, so some measures should be taken to ward off evil spirits and seek peace.

The fourth day of July is also the day to welcome the kitchen god, who is going home. People will set off firecrackers to enliven the atmosphere to welcome the arrival of Kitchen God.

Different places have different customs, and each custom has its historical and cultural background.