He graduated from Tokyo Imperial University with a legal degree and passed his civil service examinations in 1896.

On 2 March 1932, Minami became Governor-General of Taiwan,[1] but served in that post for less than three months before being replaced on 26 May, following the May 15 Incident to become Communications Minister in the Saito administration.

He was the first cabinet minister to have been appointed from Toyama Prefecture, and served in this post for two years and two months.

In 1943, Minami served as chairman of the National Language Council, a government body established to standardize the Tōyō kanji and Modern kana usage to simplify education.

[2] He was also a member of the Privy Council, where he earned the enmity of the military by his outspoken remarks against Japanese militarism.