Born in the Los Angeles suburb of Burbank, Aiso was an excellent student, despite encounters with anti-Japanese prejudice. He later described one of his first memories as being called a "Jap" by an elderly woman on a streetcar, explaining the amount of effort he put into his schoolwork was largely to counteract such comments. He was elected student body president of his junior high school in 1922, but the victory proved to be short lived: parents protested a Japanese American holding the position, and student government was suspended until Aiso left the school. He went on to attend Hollywood High School, where he drew national attention when he won the school's oratorical competition on the U.S. Constitution in 1926. However, he was once again forced to step down, when he was told he could not compete at the national championship and would instead have to coach his runner up.
Education and career
After graduating at the top of his Hollywood High School class in 1926, Aiso spent a year in Japan, studying Japanese at Seijo University in Tokyo. He returned to the United States after receiving a scholarship to attend Brown University, where he captained the debate team and majored in economics, graduating cum laude and serving as class valedictorian in 1931. He continued his studies at Harvard Law School, completing his degree in 1934. Between 1935 and 1952, he worked in private practice in Los Angeles and New York. In 1936, he spent another year in Tokyo, working with Japanese banks on behalf of his U.S. law firm, and while there he studied Japanese law at Chuo University. From 1937 to 1940, he worked for the British American Tobacco Company in Japanese-occupied Manchuria. After his return to the United States, Aiso was drafted into the army, reporting for active duty in April 1941. Originally stationed at Fort MacArthur, Aiso was assigned to menial tasks due to discrimination, and was working in the motor pool when his proficiency in the Japanese language was recognized by Fourth ArmyG-2 officer, Capt. Kai E. Rasmussen, who was tasked with developing a Japanese language school, and transferred Aiso to the hastily formed Military Intelligence Service Language School. Recruited by MISLS head Lt Col John Weckerling as an instructor at the school, Aiso, then a Private First Class, couldn't be expected to teach officers, and Japanese Americans were prohibited from being commissioned at the time, so he was to be discharged, transferred to Reserve service, and hired as a War Department Civilian. Aiso distinguished himself in his role, earning praise from his commanders and his fellow instructors, and was soon appointed the Director of Academic Training, a position normally held by a Lieutenant Colonel. When the Chief of Army Intelligence, Gen Clayton Lawrence Bissell, visited the school in 1944, he was outraged that a civilian was placed in command of military personnel, and went back to Washington to demand a direct commission for Aiso to Major. In this position, he became the highest-ranking Japanese American in the United States Army during the Second World War, eventually separating from active duty with the rank of lieutenant colonel. Under his inspiring leadership as director of academic training, the MISLS rapidly expanded. He recruited and trained a staff of over 150, developed course materials, and set the highest academic standards. The more than 6,000 graduates contributed immeasurably to the American victory over Imperial Japan and to winning the peace that followed. After the Allied victory in August 1945, Aiso refocused the MISLS curriculum to prepare students for roles in the occupation of Japan. In January 1946, he would transfer to Gen Douglas MacArthur's staff as a legal assistant under MacArthur's G-2 chief, Gen Charles A. Willoughby, working in the investigation and enforcement of the political purge dictated by the Potsdam Declaration. Aiso was released from active duty and returned to Los Angeles in February 1947, returning to private law practice. He would later be promoted to a colonel in the Army Reserve, before retiring in 1965. In 1950, he received an honorary master's degree from Brown University. In 1952, he served as a Commissioner for one year. Aiso was then appointed to the Los Angeles Municipal Court in 1953, where he served until he was elevated to the Los Angeles Superior Court in 1957. He was the first Japanese American to enter the California State Judiciary when then Governor Ronald Reagan appointed Aiso as an Associate Justice of the California Court of Appeal, Second Appellate District, on November 4, 1968.
John Aiso died December 29, 1987, from a head injury sustained in an attempted mugging. Aiso, 78, was filling his car at a Hollywood gas station when he was attacked and knocked to the pavement; he died two weeks later in a Burbank hospital.
