Former Residence of Yoshida Shigeru (Oiso)

Shigeru Yoshida (吉田茂, 1878–1967) served as Prime Minister of Japan for two terms spanning five cabinets (1946–1947 and 1948–1954), making him the dominant political figure in Japan's immediate postwar era. A career diplomat before the war, Yoshida served in consular and ambassadorial posts across China and Europe. During the war years, he was associated with the "peace faction" (和平派) that sought to end hostilities, and was briefly detained by the Kempeitai (military police) in 1945 for his involvement in efforts to negotiate an early surrender.

After Japan's defeat, Supreme Commander for the Allied Powers Douglas MacArthur selected Yoshida — with his pro-Western orientation and English-language ability — as a suitable leader for the occupied nation. As Prime Minister, Yoshida pursued a pragmatic strategy of focusing Japan's limited resources on economic recovery while relying on the United States for defense, a policy framework later known as the "Yoshida Doctrine" (吉田ドクトリン).

His greatest diplomatic achievement was the San Francisco Peace Treaty (サンフランシスコ講和条約), signed on September 8, 1951, which formally ended the state of war between Japan and 48 Allied nations and restored Japanese sovereignty when it came into effect on April 28, 1952. At his Oiso estate, Yoshida prepared for the peace conference, receiving advisors and diplomats in the elegant reception rooms. The Kabuto Gate (兜門), the estate's distinctive entrance gate designed to resemble a samurai helmet, was built in 1954 to commemorate the successful conclusion of the peace treaty and is also called the "Treaty Gate" (講和門).

The Oiso residence served as far more than a private home. After Yoshida's retirement from the premiership in 1954, politicians, bureaucrats, and business leaders made regular pilgrimages to Oiso — a practice known as the "Oiso pilgrimage" (大磯詣で) — seeking the elder statesman's counsel. Prominent among the callers were members of the "Yoshida School" (吉田学校), the group of largely ex-bureaucrat Diet members whom Yoshida had brought into politics while party president and who went on to lead postwar Japan — above all the future Prime Ministers Ikeda Hayato (池田勇人) and Sato Eisaku (佐藤栄作), whose own factions later produced Tanaka Kakuei (田中角栄), Ohira Masayoshi (大平正芳), and Miyazawa Kiichi (宮澤喜一).

The estate grounds contain several historically significant structures. The Shichikendo (七賢堂, Hall of Seven Sages) was originally built by Ito Hirobumi in 1903 at his nearby Oiso villa as the "Hall of Four Sages" to enshrine four Restoration statesmen (Sanjo Sanetomi, Iwakura Tomomi, Okubo Toshimichi, and Kido Takayoshi); after Ito's death his widow added Ito himself, making five. The hall was relocated to the Yoshida estate in April 1960, where Yoshida added Saionji Kinmochi, and it became the Hall of Seven Sages when Yoshida himself was enshrined after his death. A bronze statue of Yoshida Shigeru, erected by local supporters, stands on an elevated point of the grounds gazing toward San Francisco across the Pacific — symbolizing the peace treaty that defined his legacy.

The main residence (本邸) was designed by the celebrated architect Yoshida Isoya (吉田五十八, no relation to Shigeru) in a modern sukiya-zukuri style. The all-cypress building was constructed by master carpenters from Kyoto who specialized in imperial palace construction. The interior featured a Gold Room (金の間) and Silver Room (銀の間) used for receiving state guests and foreign dignitaries, including former West German Chancellor Konrad Adenauer. The Japanese garden was designed by the internationally acclaimed landscape architect Nakajima Ken (中島健).

On March 22, 2009, a fire of unknown origin destroyed the main building. While the loss was devastating, the Kabuto Gate, Shichikendo, bronze statue, and Japanese garden survived intact. Oiso Town, working with Kanagawa Prefecture and supported by public donations, undertook a meticulous reconstruction effort, using original architectural drawings by Yoshida Isoya, historical photographs, and testimony from surviving craftsmen. The faithfully restored residence opened to the public on April 1, 2017, as the Oiso Town Local History Museum Annex (大磯町郷土資料館別館), situated within the Kanagawa Prefectural Oiso Joyama Park (県立大磯城山公園).

Today the site preserves both the architectural legacy of mid-20th century Japanese residential design and the political history of the men who shaped postwar Japan from this seaside retreat.