Hosokawa was born on Jan. 14, 1938, in Kyushu, Japan. The grandson of pre–World War II prime minister Fumimaro Konoe, Hosokawa attended Sophia University, graduating in 1963. Intent on a career in journalism, he took a job with the liberal newspaper Asahi shimbun. A run in 1969 for election to the lower house of the Diet was unsuccessful. However, in 1971, with strong support from the ruling LDP, Hosokawa was elected to the less powerful upper house, where he served for 12 years.

In 1983 Hosokawa was elected governor of Kumamoto prefecture on Kyushu island. While serving as governor, he pursued an aggressive economic policy and strengthened environmental laws but was often frustrated by the powerful bureaucracy of the central government. In 1992, calling for electoral reform and an end to political corruption and one-party rule, Hosokawa formed the Japan New party. The party was quickly embraced by people around the country who were tired of the scandals and internal dissension plaguing the Liberal Democrats.

In 1993 a coalition of seven dissident LDP factions and opposition parties in the House of Representatives elected Hosokawa prime minister, making him the first non-LDP premier since 1955. Once in office, Hosokawa engineered passage of a bill to restructure the electoral system in an effort to limit political corruption and increase the relative voting strength of urban areas. He resigned in April 1994, however, amid charges of financial impropriety leveled at him by the LDP.