Kimi ga yo wa iku yorozuyo ka kasanubeki itsunukigawa no tsuru no kegoromo - Kinyo Wakashu(English Translation & Meaning)

君が代は幾万代か重ぬべき
いつぬき川の鶴の毛衣

Roma-ji: Kimi ga yo wa iku yorozuyo ka kasanubeki itsunukigawa no tsuru no kegoromo
English Translation: Our lord's reign, how many
ten thousand ages will it
layer one on one,
like the cranes of Itsunuki River
and their robes of feathers
Meaning: How many ten thousand ages will our lord's reign layer one upon another, like the feather robes of the cranes on the Itsunuki River?
Commentary: Book Five Celebration Poems 323

Likening the feathers of the cranes on the Itsunuki River to robes, the poem asks how many ten thousand ages the sovereign's reign will layer one on another, as robes are layered. Weaving in the crane, said to live a thousand years, and stringing together words of clothing, kasanu, to layer, nuki, the weft, and kegoromo, feather robe, it celebrates the long reign.
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.

First line, 'kimi ga yo wa', means our lord's reign, the same first line as poems 311 and 313 in this book.
Second line, 'iku yorozuyo ka', means how many ten thousand ages, ka binding with the attributive beki in the third line.
Third line, 'kasanubeki', means will it layer, using the conjectural beshi. The poem breaks after the third line and the lower half is inverted.
Fourth line, 'itsunukigawa no', is the name of a river, nuki suggesting the weft of a weave, related to 'layer' in the third line and 'feather robes' in the final line.
Final line, 'tsuru no kegoromo', is the crane's feathers seen as a robe, closing with a noun; the crane, said to live a thousand years, shows the length of the reign.
Source: Kinyo Wakashu
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