Furthermore, after Kento-shi (Japanese envoy to Tang Dynasty China) was abolished, the decline of Tang culture and uplift of the Kokufu Bunka (Japan's original national culture) activated events such as Uta-kai (poem competitions) and utaawase (poetry contests), and organization and establishment of rules of Kadai (subjects of waka Japanese poem) and Daii (meanings of subjects), and specialization in the study of classics and knowledge of court rules, ceremony, decorumts regarding waka that were considered to be necessary to compose better waka developed.
更に遣唐使廃止後の唐風文化の衰退と国風文化の高揚が、歌会・歌合などの行事を活発化させ、それにつれてより良い和歌を作成するために必要であると考えられた歌題・題意の組織化と規範化、和歌に関する古典・有職研究の専門化が進展した。