The Ryukyuan dance is divided into four categories: Classical dance (Koten buyo), Mixed dance (zo-odori), Folk dance (Minzoku buyo), and Creative dance (Sosaku buyo).

The classical dances rapidly developed under the royal government at Shuri (1429 - 1879) in Ryukyu Kingdom. The ‘elders' dance,’ ‘young men’s dance’ and ‘women's dance’ were performed mainly for the Chinese envoys, while the ‘young men's dance’ was mainly performed to entertain officials from Satsuma (= Kagoshima). Therefore dance was an important diplomatic instrument for the royal government. The dancers were only men from the elite ranks of society, strictly supervised by a government Minister of Dance and due to this historical fact, Ryukyuan dances became highly refined.

The Ryukyu Kingdom ended when the Meiji government abolished ‘hans’ and created prefectures (1879). The dancers lost their jobs and started small street theaters where they extended the stories to the lives of ordinary people to create innovative dances. This is how the zo-odori dances were born.

Folk dance was passed down from generation to generation at different places all around the islands of Ryukyu and it retains its traditions and sacred rites still now. After the war, a number of choreographers reflected their new generations on creative dance embodying the traditional elements of Ryukyuan dances.

Reference (http://rca.open.ed.jp/city2000/ryubu/explan/explan.html)

琉球舞踊は古典舞踊、雑踊り、民族舞踊、そして創作舞踊の四つに分類されます。

古典舞踊には中国から来た冊封使に披露された老人踊り、若衆踊り、女踊りと、主に薩摩藩の役人に披露された二才踊りがありますが、政治的な活用価値が高かったため、朱里王府の元で急速に発展していきました。躍り手は全て、士族出身のエリート家系の男性と定め、政府の機関「踊奉行」に厳しく監視させていたことで、すばらしく洗練されていったのです。

明治政府による廃藩置県で琉球王朝に終わりが来たことで、踊り手が仕事を失い、村の小さな劇場で新たなスタートを切ることになりました。そこで、一般人の生活を舞台にした革新的な踊りが生まれました。これが雑踊りです。

民族舞踊は沖縄の島々で世代から世代へ、伝統と儀式の要素を残しつつ受け継がれました。そして戦後、多くの舞踊家たちが伝統を守りながら新たな世代の生活に反映させ、創作舞踊を作り上げていきました。。

The eisaa, a folk performing art, is a dynamic, spirited dance intrinsic to a midsummer festival called Bon, or Festival of the Dead, which takes place for three days from July 13 -15 of the lunar calendar. A dance of Okinawa Island and the surrounding smaller islands, it is basically a circular dance composed of both men and women.

The musical instruments used in the eisaa including the sanshin, large barrel drums, and small hand drums, or paranku, the even smaller ones. Otherwise there are some eisaa which don't involve any musical instrument above but only dances in the north part of Okinawa main island and it is said that this is the original style of eisaa.

The men play the sanshin and beat vigorously on the drums as the women dance to the rhythms. On the night of July 15, after the ancestral spirits have returned to the world of the dead, the dancers of each village gather in the courtyard of the kami ashagi (major site of community worship) and begin the eisaa. After offering the first dance to the village gods, the dancers make the rounds of the homes in the village, perfoming the eisaa dance.

The eisaa originated from a group dance called 'esa omoro', to which Buddhist songs and dances were later added. Its present name, eisaa, for the Bon Dance is derived from the phrase "eisaa eisaa hiyaruga eisaa" which is a refrain in the Buddhist songs. This is how it is believed and has been the strongest explanation.

Though regarded today as entertainment, the eisaa originally had an important religious function of giving repose to the dead. An eisaa performance on street corners and at homes of villagers was comparable to performing a memorial service for village ancestors. Thus, the eisaa always began with songs which invoked the Buddha.

It was only later that popular Okinawan folk songs today came to be included in the eisaa song repertoire. Moreover the Creative eisaa style became popular lately and Okinawan pop songs included accordingly.

Reference (http://okinawa.com/research/performing-arts/eisa

http://www.zentoeisa.com/about-eisa.html)

沖縄本土の盆踊りにあたる沖縄の伝統芸能のひとつで、活動的で勇ましい踊りが特徴的です。主に各地域の青年会がそれぞれの型を持ち、旧盆である7月13日から15日の夜に地域内を踊りながら練り歩きます。

一言で「エイサー」と言ってもその形態はいくつかに分類され、現在ほとんどの青年会が、大太鼓、締め太鼓、更に小振りのパーランクーを中心とした「太鼓エイサー」であり、沖縄県中部が最も盛んな地域と言われています。また、太鼓を使わない「手踊りのみのエイサー」もあり、本島北部にいくつか存在しますが、これがエイサーの最も古い形ではないかと言われているそうです。

エイサーの由来はいくつかありますが、一番有力な説は現存する「エサオモロ」という集団舞踊のリズムに念仏形式の踊りが定着したものだと言われています。エイサーという名前はその囃子言葉である「エイサー、エイサー、ヒヤルガエイサー」から、そう呼ばれるようになったそうです。

今日エイサーはエンターテイメントの要素が強いですが、元々は亡くなった方々の魂に休息を与えるという、宗教的に重要な役割を担っていました。村の通りや軒先で踊られるエイサーはご先祖様への慰霊祭なのです。ですからエイサーは仏様を呼び出す歌とともにいつも始まります。

人気の沖縄民謡がエイサー曲のレパートリーに加わったのはずっと後になってからで、更に近年では、エイサーの型を取り入れ、音楽にはポップスを使用するし、また、衣装も独創的な「創作太鼓」のグループも数多く存在するようになりました。