The most distinguished surname in Japan is the Fujiwara family.
The earliest surname in Japan was found in 669 AD and was the Fujiwara clan. The ancestor of the Fujiwara clan was named Nakatomi Kamazu, and "Nakatomi" was his surname. Nakatomi Kamazu was born into a wealthy Japanese family. After his birth, it was the period when the Tang Dynasty was established and prosperous. Sino-Japanese cultural exchanges prompted Japan to launch the Daika Reform Movement. Nakatomi Kamazu participated in the Daika Reform and helped the emperor defeat the then The powerful minister Suga gained the power to rule the country.
When Nakatomi Kamazu died, Emperor Tenchi (reigned from 661 to 671) gave the court minister the surname Fujiwara to express his gratitude to Nakatomi Kamazu. This is the only surname among the four major surnames that has nothing to do with the royal family.
There are four oldest surnames in Japan, namely: Minamoto, Taira, Fuji, and Tachibana. They are all close relatives or dignitaries of the emperor. They later derived the following surnames: Kiyowa Genji, Omi Genji, Fujiwara, Taira Kiyomori, Taira Shomon, etc., and only the Fujiwara clan derived: Sato, Ito, Kato and other surnames. Those with surnames like this have been passed down to Japan's established aristocrats.
Because Japanese surnames are highly variable (surnames can be changed due to starting a new family business, branching of a family group, or adoption relationship, etc. This is also the main reason for the large number of Japanese surnames). Therefore, the origin of Japanese surnames is very complicated and there are different opinions. Generally speaking, Japanese surnames can be divided into two categories: those that have existed since ancient times and those that were created after the "Miao Character Bi-nam Order".