"The earliest documentation of fireworks dates back to 7th century China where they were first used to frighten away evil spirits with their loud sound (鞭炮/鞭砲 biān pào) and to pray for happiness and prosperity. Eventually the art and science of firework making developed into an independent profession. In ancient China, pyrotechnicians (firework-masters) were respected for their knowledge and skill in mounting dazzling displays of light and sound. A record in 1264 states that the speed of the rocket-propelled 'ground-rat' firework frightened the Empress Dowager Gong Sheng during a feast held in her honor by her son Emperor Lizong of Song (r. 1224–1264). By the 14th century rocket propulsion was common in warfare, as evidenced by the Huolongjing compiled by Liu Ji (1311–1375) and Jiao Yu (fl. c. 1350–1412). However, in China, fireworks for ceremonies and celebrations were mostly for royalties and the rich before the 14th century. It was only in the Ming Dynasty that any event for common people — a birth, a wedding, a business opening, or a New Year's Eve celebration — became a fitting occasion for fireworks and other noisemakers. Amédée-François Frézier published a "Treatise on Fireworks" in 1706, covering the recreational and ceremonial uses of fireworks, rather than their military uses. The book became a standard text for fireworks makers. Music for the Royal Fireworks was composed by George Frideric Handel in 1749 to celebrate the peace Treaty of Aix-la-Chapelle, which had been declared the previous year." -From Wikipedia
A Chinese monk named Li Tian, who lived near the city of Liu Yang in Hunan Province, is credited with the invention of firecrackers about 1,000 years ago. The Chinese people celebrate the invention of the firecracker every April 18 by offering sacrifices to Li Tian. During the Song Dynasty, the local people established a temple to worship Li Tian.
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There is no mention of any specific person, but it was invented in China, around the time of the Han Dynasty (206-220 BC)