Kimi ga yo wa kagiri mo araji mikasayama mine ni asahi no sasamu kagiri wa - Kinyo Wakashu(English Translation & Meaning)

君が代は限りもあらじ三笠山
峰に朝日のささむ限りは

Roma-ji: Kimi ga yo wa kagiri mo araji mikasayama mine ni asahi no sasamu kagiri wa
English Translation: Our lord's reign will know
no end at all, I am sure,
as on Mount Mikasa
upon its peak the morning sun
shall go on shining down
Meaning: Our lord's reign will have no end, so long as the morning sun shines on the peak of Mount Mikasa.
Commentary: Book Five Celebration Poems 325

So long as the morning sun shines on the peak of Mount Mikasa, the sovereign's reign will never end, the poem says. Taking the sun that rises unfailingly every morning as a sign of the reign's endurance, it celebrates through a majestic scene. Kasa, umbrella hat, in Mikasa and sasu, to shine or to hold up an umbrella, are related words.
Some manuscripts of the Kin'yōwakashū give the headnote 'Composed on the theme of celebration at a poetry contest at the house of the former Chancellor of Uji.' It opens with the same two lines as the Kokinshū poem of Ise Province for the Great Thanksgiving, which says the reign will know no end though one count every grain of sand on the beach of Nagahama.
It takes up Mount Mikasa from poem 322 in this book, and its morning sun echoes poem 316 and the closing poem, 333.
From poem 322 through poem 326 in this book come poems celebrating a thousand and ten thousand ages, mingling words tied to the Fujiwara clan such as Mount Mikasa, Ame no Koyane and wisteria.
The author, Masafusa, is Ōe no Masafusa. A son of Ōe no Narihira, he rose to Provisional Middle Counselor. Known as the foremost scholar of his day, he was called Gōsotsu from his service as Provisional Governor-General of Dazaifu, and one of his poems appears in the Ogura Hyakunin Isshu.

First line, 'kimi ga yo wa', is the same first line as poem 323 and the preceding poem, 324, in this book.
Second line, 'kagiri mo araji', means there will be no end, using the negative conjecture ji. The poem breaks after the second line and the lower half is inverted, and the word kagiri, end, recurs in the final line.
Third line, 'mikasayama', is a poetic place in Yamato, the mountain behind the Kasuga Shrine, also sung in poem 322 in this book.
Fourth line, 'mine ni asahi no', means the morning sun on the peak; poems 316 and 333 in this book also sing of the morning sun.
Final line, 'sasamu kagiri wa', means so long as it shall shine, sasu, to shine, being related to the kasa of the third line. Repeating kagiri from the second line, it says the reign will be endless as long as the sun shines.
Author: Oe no Masafusa
Source: Kinyo Wakashu
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