Background

Shinto* Muso-ryu jo is said to be the oldest style for using a stick (jo) in combat in Japan. It was founded in the early 17th century by Muso Gonnosuke Katsuyoshi, an exponent of Tenshin Shoden Katori Shinto-ryu.
Shinto Muso-ryu oral tradition maintains that Gonnosuke once fought Miyamoto Musashi, one of the most famous swordsmen of the time, with a staff (bo) in a training match and was defeated by Musashi’s cross-block (jujidome) technique.

Legend says

According to legend, Gonnosuke was dissatisfied with this outcome and
retired to Mt. Homan, in what is now Fukuoka Prefecture,
in Kyushu, where he engaged in a series of religious austerities, all the while contemplating the reasons for his defeat.

Finally, he received "divine" inspiration about a new method of using a staff-like weapon, making it shorter (50 1/4") and thinner (7/8") for more rapid manipulation. He devised a number of techniques for this new weapon, which he called a stick (jo) (as opposed to staff or bo), that included the use of the thrust (tsuki) of a spear, strike (utsu) of a sword and staff and sweep (harai) of a naginata.
Factual documents of the style (ryu) are quite rare.
It is said that there is a record at Tsukuba Shrine, in Ibaragi Prefecture, that reports that Gonnosuke was able to defeat Musashi in a rematch. This story is not recorded elsewhere, however, outside fictional novels, and may not be factual.

There are a total of 64 techniques in Shinto Muso-ryu jo
that are divided into a number of sets, each with a different character.
Training is systematic and develops the exponent’s technical skills and psychological abilities, from body movement and weapons handling to the proper use of timing, targeting, and distancing, and intense mental or spiritual training,
all to enable the exponent to successfully use the weapon in mortal combat.