Seisan

Other names	Sesan, Seishan, Sei-Shan, Jusan, Hangetsu
Martial art	Karate, Tang Soo Do
Place of origin	Okinawa, Ryukyu Kingdom
Creator	Yamaza Bin Yamazu

The karate kata Seisan (alternate names: Sesan, Seishan, Jusan, Hangetsu) literally means '13'. Some people refer to the kata as '13 Hands', '13 Fists', '13 Techniques', '13 Steps' or even '13 killing positions', however, these names have no historical basis.

Seisan is thought to be one of the oldest kata, being quite spread among other Nahate schools. Shito-ryu has its own version and different versions are now practised even in Shurite derivatives like Shotokan (called Hangetsu) and in Wado-ryu (called Seishan). Isshin-ryū also adopted this kata. This kata is also practiced in Korean styles such as Tang Soo Do and Soo Bahk Do and is called Sei-Shan or Seishan in Korean. Due to its difficulty, this kata is often reserved for advanced students.

The following styles have made this kata a formal part of their curriculum.

There are numerous theories regarding the name of the kata. These include the number of steps originally in the kata, the number of different types of 'power' or 'energy' in the kata, the number of applications, or that the kata represents defence against 13 specific types of attack. The most likely explanation is the number of non-repeating techniques contained within the kata. It is believed Seisan derives from Yong Chun White Crane Boxing from Fujian Province in Southern China, where the form is known as 'Four Gate Hands'. (This is completely unproven and uncorroborated. There are some other Chinese styles having a form called 'Shisan' (13) in their curricula, but a link from a specific kung-fu form to Okinawan Seisan has never been established.)

Versions of Seisan taught today have roots in Shuri-te, Naha-te and Tomari-te streams of karate (that is the karate that was traditionally taught in the Okinawan towns of Shuri, Naha and Tomari respectively).

This is the second of the three kata of Pangai-noon learned and then taught by Kanbun Uechi. It it has obvious foundations in Sanchin, relying on primarily the "Sanchin stance" or sanchin dachi (三戦立ち^?) and opening as does Uechi-Ryū Sanchin for three strikes then later returning to these strikes near the end of the kata. Compared with other versions of the kata, Uechi-Ryū's is very different. The kata introduces some of the basic techniques such as knee strikes, the one-knuckle punch shōken zuki (小拳突き^?), spearhand nukite (貫手突き^?), and the front kick shōmen geri (正面蹴り^?) which were then incorporated in the "bridging" kata created by Kanbun Uechi's son and senior students between Sanchin and Seisan. In modern Uechi-Ryū, it is the fifth kata learned and the one tested for the first "black belt" or shodan (初段^?) grade.

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Wikipedia