Japan is called the "land of the rising sun" because from China it appears that the sun rises from the direction of Japan. The Japanese people call their country "Nippon" or "Nihon," which literally translated means "source of the sun." It is loosely translated into English as "land of the rising sun."
There is nothing but the Pacific Ocean for miles beyond Japan, with nothing else visible from a continental view. The Chinese took in this view from the shoreline, which created the illusion that the rising sun came from Japan, earning the country the nickname. The name also indicates the location of Japan with relation to China. It is directly east of the Chinese coastline.
During Japan's early development, China had a large influence on the emerging Japanese culture. It is believed that the Japanese took the name Nihon for their country because of how the country was seen from a Chinese perspective. The Chinese gave Japan the name during the Sui Dynasty. The Japanese version of the name, Nippon, was officially adopted in documents and manuscripts during the Taika Reform in 645 AD. This provided a way to centralize the country's government rather than allow it to continue as a conglomeration of privately owned lands.