The context of that is the influence on disciplinary methods heavily borrowed from the Imperial Japanese Army's corporal punishment.
その背景には The context
旧日本軍の体罰 Japanese Imperial Army's corporal punishment
を多用する heavily borrowed
訓練法の影響がある Influence of the training method
その背景には旧日本軍の体罰を多用する訓練法の影響がある
The context of that is the influence on disciplinary methods heavily borrowed from the Imperial Japanese Army's corporal punishment.
「日本はかつて学校教育で体罰を容認する社会風土があった」
There was once a climate of acceptance in Japanese society towards the use of corporal punishment in Japanese schools.
オーストラリア 
