Kukishin-ryū jōjutsu developed sometime during the Genna period (1615 – 1624) by the 11th Sōke, Okuni Kōgenta Yukihisa.
The Jō-bō (杖棒) could in the old days sometimes had a stone or iron weight at one end. Because of this reinforcement, all our basic jōjutsu techniques today have two versions, so you can choose whether they wanted to strike with the reinforced end or not.
During the latter part of the Edō period the jō-staff was more popular and at some point it was decided to remove the weight.
There are 3 types of jō-bō in Kukishin-ryū, the two most common are maru-bō (round staff; 丸棒) and Hakkaku-bō (octagonal staff; 八角棒). The third type is called Shaku-jō (copper staff; 錫杖), a rod that monks used on their hikes.
Originally Kukishin-ryū jō-bō is about one shaku (feet, ie 30.3 cm) shorter than what one was long, (eg if you were 5 feet long rod was 4 feet (~ 120 cm) or if you are 6 foot-long rod was 5 feet long (~ 150 cm)) to compare to modern standards jō-bō which can be bought in store and which is 124 cm long. The staff diameter was usually 27mm (9 bu).