In older texts, this was read askun'yomi as日の本(Hinomoto). Theon'yomi readingsNippon andNihon became more common in theHeian period, with both persisting into modern use.[3] TheNihon reading appears to be the most common in everyday Japanese usage.[4]
Thisappellation comes fromPrince Shōtoku's famous letter fromPrince Shōtoku toEmperor Yang of Sui sent via theJapanese mission to Sui China in 607, wherein we see the first mention of Japan as theLand of the Rising Sun, and a description of China asLand of the Setting Sun:
日出處 (literally “sun +emerge +place”) here refers to Japan, while日沒處 (literally “sun +sink + place”) refers toChina. "Sun emerge place" both refers to theeastwardposition of Japan relative to China, and metaphorically places the Yamato Kingship during Empress Suiko's reign on a similar footing as to the Sui dynasty under Emperor Yang's rule.
The earliest date for the specific spelling日本(literally“sun source”) instead of the periphrastic日出處 (literally “sun emerge place”) may be 664, as mentioned in a fragment of the 733 text海外国記(Kaigai Kokki,“Record of Overseas Countries”), describing a letter given in 664 to a Tang emissary arriving inDazaifu.[5] However, it remains an open question whether this instance of日本 might have been a change in name that happened between the actual event in 664 and the recording of that event in 733.[5] More certainly, the Japanese sourceShoku Nihongi relates that a 702 or 703 mission from Japan to the Tang court requested that the Chinese change the official name from倭(Wa) to日本(Nippon), and this appears to be corroborated by accounts in the Chinese sourceOld Book of Tang.[5][6]
Despite the spelling, the term may have been read out as the older nameYamato for some time afterwards, as suggested by kana glosses in sources such as theMan'yōshū poetry anthology of 759.[2][7]