Kurosu Harutsugi (黒須春次) was born on March 13, 1888, and died March 15th, 1973. He was born in a farming family, but due to his father’s illness, he had to help him from a very young age. At the age of 18, he began studying Araki Shin-ryu jujutsu in 1906, from Hayashi Hikojiro. His body trained in jujutsu, he was accepted into an artillery regiment. He received a menkyo kaiden in Araki Shin-ryu in 1921 from Urano Kasutsugu Nobutaka.
[NOTE: There is more than one line of Araki Shin-ryu, that bear little relationship to one another. Perhaps the most famous is a a ryuha started by Araki Buzaemon, which has a complicated relationship to the original Araki-ryu torite-kogusoku of the founder, Araki Muninsai.]
A few years after beginning his study of Araki Shin-ryu, he also began training in Shinto Rikugo-ryu jujutsu, an amalgam of a number of older schools, and eventually receiving a rank of 4th dan in 1922. Although kata based, it focused on hand-to-hand combat and was, for a period of time, a rival of the Kodokan. (The last known teacher of this school is Shiigi Munenori of the Ichigido).
Kurosu was not satisfied by jujutsu alone, obviously needing to compete. Only judo at that time allowed shiai and he entered the Kodokan in 1913. Very soon afterwards, he was ‘tested’ in a match with four seniors, and after defeating them, was awarded a judo fourth kyu (NOTE: which meant a lot more in those days). He established his own judo dojo in the Shinjuku area of Tokyo in 1914 (remember, he was already had high rank in two jujutsu schools, which he continued training–apparently, this was rather common in those days, enabling the Kodokan to incorporate jujutsu practitioners quickly into their organization). In fact, he was already considered skilled enough that in 1916, he was appointed a judo instructor of the Kenpeitai.