Upon graduation, he began working for the Ministry of Finance and served in the navy during the Second World War as part of a programme that offered a shortened period of service to young, educated individuals in roles considered essential to the country.

[5] After Iichirō's retirement in 1974, he gave in to long-standing family pressure; and his career in politics began with his election to the House of Councilors (HC) in the Diet.

Despite family pressure, he was interested in building a life outside the arena of Japanese politics; and his sons also grew to become independent-minded men.

Iichirō is the father of Yukio Hatoyama, who was the former Prime Minister, following a win by the opposition coalition in the 2009 elections.

Kunio Hatoyama, like his brother Yukio, may be described as a fourth generation politician [1] and most recently the Minister of Internal Affairs and Communications.