Because all Japanese words end in one of only a few vowels, rhyme is not important in Japanese poetry. Instead, a particular balance of syllables is used, arranged over a set number of lines. This form also distinguishes poetry from prose. Perfection of phrasing in cleverly written short verses is characteristic of Japanese poetry. This is exemplified in styles such as the tanka (31 syllables in alternating lines of five and four syllables each) and the haiku (17 syllables).
Intrinsically, there is no epic poetry in Japan, although the choka was a form of long poem constructed by extending the tanka form. These and other styles were fixed in poetic codes, established at court, and they encouraged an aristocratic trend in poetry.
The earliest collection of poems or songs is in the Koji-ki (Records of Ancient Matters) dating from AD 712, some of which were later transcribed and produced as tankas.
From the second half of the eighth century comes the Man-yoshu, an anthology of poetry containing mostly tankas but with some excellent examples of the choka style, particularly by Hitomaro. The poems in this collection differ greatly from later more delicate styles. They possess considerable emotional force and demonstrate a wide range of forms and themes.
In the classical literature of the Heian period (784-1185), kana became popular. The first major work in kana was the Kokinshu, a collection of poems largely expressing love themes, emphasizing the melancholy aspect of love. The poems, most in the tanka form, are of great beauty and this collection remained the canon of poetic writing for centuries. However, the formality of the style tended to stifle any originality of expression.
During the medieval period in Japan, a new form of poetry arose. The renga (linked verse) were based on the tanka and developed from a popular tradition where two people would alternately add sets of lines to the poem. This style was formalized by the court poets and consequently became a respectable poetic form.
Under the Tokugawa shogunate (1603-1867), the haiku style emerged. Originally the opening lines of a renga (called Hokku), it gradually emerged as an independent verse form. The greatest master of the haiku was Matsuo Basho whose most popular work is Oku no Hosomichi (The Narrow Road through Deep North), published in 1694.
A form of comic renga, the haikai renga, developed in the sixteenth century and continued to the end of the Tokugawa period. In the early nineteenth century the poet Rai Sanyo wrote beautiful verses in the Chinese language but in general Japanese writers were not prolific in the nineteenth century.