By the 1930s it became known for housing political prisoners, including many communists and other dissenters who fell foul of the Peace Preservation Laws in the 1930s and 1940s.

After the conclusion of the trials, Sugamo Prison was used to incarcerate some of the convicted and was the site of the execution of seven inmates sentenced to death by hanging on December 23, 1948.

After being captured and re-purposed by Allied forces, the facility was operated by the United States’ Eighth Army.

[4] After the end of the occupation of Japan, Sugamo Prison passed to Japanese civilian government control.

In 1978, the Sunshine 60 Building, at its completion the tallest skyscraper in Japan, was built on the former site of Sugamo Prison.