From Joe Swifts, Roots Of Shotokan:
Funakoshi's Original 15 Kata
Wanhsu (Wansu or Enpi)
This kata is said by many to have been brought to Okinawa by the 1683 Sappushi (Chinese Imperial envoy) Ji Wang (Jpn. Oshu, 1621-1689). It is possible that it is based upon or inspired by techniques that were taught by Ji Wang. A move from this kata is here demonstrated by Funakoshi.
The problem with this theory is that why would such a high ranked government official teach his martial arts (assuming he even knew any) to the Okinawans? Also, Ji Wang was only in Okinawa for 6 months(Sakagami, 1978).
Ji Wang was originally from Xiuning in Anhui (a geographic section of west central China), and was an official for the Han Lin Yuan, an important government post (Kinjo, 1999). In order to become an official for the Han Lin Yuan, one had to be a high level scholar, and pass several national tests (Kinjo, 1999). Just preparing for such a position would be such a time consuming task that is would all but rule out the practice of martial arts. However, assuming that Ji Wang was familiar with the martial arts, the Quanfa (a generic Chinese term referring to martial arts) of Anhui is classified as Northern boxing, while the techniques of the Okinawan Wansu kata are clearly Southern in nature (Kinjo, 1999).
So, was Wanshu named after Ji Wang, or someone else? This is as yet unknown. However, in the Okinawan martial arts, kata named after their originators are not uncommon. Some examples include Kusanku, Chatan Yara no Sai, and Tokumine no Kon. It is entirely possible that this kata was introduced by a Chinese martial artist named Wang (not the offical Ji Wang). As the reader probably already knows, in the Chinese martial arts, it is common to refer to a teacher as Shifu (lit. Teacher-father). Could not the name Wansu be an Okinawan mispronunciation of Shifu Wang (Kinjo, 1999)?
Other schools of thought are that Xianhui Wu (Jpn. Go Kenki, 1886-1940) or Daiji Tang (Jpn. To Daiki, 1888-1937), two Chinese martial artists who immigrated to Okinawa in the early part of the 20th Century, may have been responsible for the introduction of the Wansu kata (Gima, et al, 1986). As a side note, Wu was a Whooping Crane boxer and Tang was known for his Tiger boxing. They were both from Fujian.