Kashii was born in Fukuoka Prefecture, graduated from the Imperial Japanese Army Academy, and became a lieutenant-general in 1931.

[1] He was the commander of the Japanese China Garrison Army from 22 December 1930 to 29 February 1932.

[citation needed] In November 1931, Kashii imposed martial law over the Japanese-ruled area of the Chinese city of Tianjin.

[2] In the February 26 Incident, the attempted coup d'état of 1936, Kashii was a leader of government forces that suppressed the revolt.

[3] Since he was sympathetic to the Imperial Way Faction, which included some of the officers who started the coup, he initially resisted military action against the revolt.