Hakaba Kitarou was first published in 1960 by Togetsu Shobo as a rental manga.
MIZUKI Shigeru penned the first three volumes, but due to disputes over pay, Mizuki quit and TAKEUCHI Kanko took over in 1961.
Takeuchi-san went on to pen all of stories between volumes 4 through 19, but Mizuki did come back for a few chapters:

• The Strangest Showdown (怪奇一番勝負, Kaiki Ichiban Shōbu) [1962]
• Johnny in the Mist (霧の中のジョニー, Kiri no Naka no Jonii) [1962]

Togetsu eventually went bankrupt, but the series got picked up by Satou Pro and was continued in 1964, With the three following stories:

• An Odd Fellow (おかしな奴, Okashi na Yatsu) [1964]
• I'm a Freshman (ボクは新入生, Boku wa Shinnyūsei) [1964]
• A Foolish Man: The Bizarre Olympics (アホな男　―怪奇オリンピック―, Aho na Otoko -Kaiki Orinpikku) [1964]

Sales were low, so Satou Pro dropped the series. Toukousha then hired Mizuki to write a sequel to "Johnny in the Mist", so that same year, Mizuki published the following chapter:

• A Secret Story (ないしょの話, Naisho no Hanashi) [1964]

This was the only chapter released by Toukousha...
However, Mizuki permanently continued the series in 1965 with the re-named sequel, "Hakaba no Kitarou", which later became known as "Gegege no Kitarou".