Why do Japanese people have beards?

It originated in Heian period, when an official from four places, Jin Mao, was at odds with Zheng Tai's then minister Fujiwara Chongan. Fujiwara's "waiters" all have moustaches, and his big partners ordered his own "waiters" to grow square beards to show that they would never compromise with Fujiwara.

Later, Fujiwara's family designed to encircle his big partner Jin Mao in the name of imperial edict, and said that Jin Mao's followers could leave safely as long as they laid down their weapons, and if they could capture or kill Jin Mao alive, they could seal the reward. More than 70 servants under Jin Mao all surrendered or defected, and all died under the leadership of Jin Mao. This spirit was rewarded by everyone including Fujiwara at that time, and Chongan personally erected a monument to commemorate them. Since then, the square beard has become the "symbol" of many warriors.

Generally speaking, in Japan, if a warrior with a good family background and high status or a descendant of a warrior (for example, someone with a family tree of 500-600 years) has a moustache, then the square beard is left by someone with a lower family background (for example, a veteran of Japan before World War II, who often had a square beard, was a businessman from his ancestors and a civilian from his grandfather).