Tanaka was born in Musashino, Tokyo,[1] and moved to Nagano at the age of 8 when his father became a professor at Shinshu University.

He graduated in the same year and briefly worked for the Mobil Oil Corporation for three months before leaving to continue his career as a writer.

[3] These included his policy of halting dam building, campaigning for environmental issues and abolishing the Nagano Press Club.

[4] These policies were designed to address ruinous public development projects that had left Nagano and many other prefectures burdened by debts.

[5] In 2002, conservative assemblymen who were upset by Tanaka's challenge to decades of pork-barrel politics forced him from office by passing a vote of no-confidence.