| 1908 | February | Born in Matsue City. Moves with his family to Iishi-mura (now Mitoya-cho), Iishi-gun, Shimane Prefecture. |
| 1920 | Enters Matsue Middle School. | |
| 1925 | Enters Matsue High School. | |
| 1928 | Enters Nagasaki Medical College. | |
| 1930 | March 29 | Mother (Tsune) dies. |
| 1932 | March | Graduates from Nagasaki Medical College. Suffers an acute infection of the middle ear. Assumes the position of assistant in the Physical Rehabilitation Department (specializing in radiology) at Nagasaki Medical College. |
| 1933 | February 1 | Enlists in the Hiroshima Infantry Regiment and proceeds to China after the Manchurian Incident. |
| 1934 | February 1 | Returns to his position at Nagasaki Medical College. |
| June | Becomes a Catholic and takes the baptismal name Paul. | |
| August | Marries Midori Moriyama. | |
| 1937 | Assumes the position of lecturer at Nagasaki Medical College. | |
| July | Recalled for military service in the war with China. | |
| 1939 | February 4 | Father (Hiroshi) dies. |
| 1940 | Returns to Japan and assumes the position of assistant professor at Nagasaki Medical College and chief of the Physical Rehabilitation Department. | |
| 1944 | Receives a doctorate in medicine. | |
| 1945 | June | Found to be suffering from leukemia and given three years to live. White blood cell count is 108,000 (normal 7,000) and red blood cell count in 300 (normal 500). |
| August 9 | Exposed to the atomic bombing and suffers a severed artery on the right side of his head. | |
| August 11 | Retrieves his wife's ashes from the ruins of their home. | |
| August 12 | Forms a relief team at Mitsuyama-machi and cares for 125 sufferers of atomic bomb disease. | |
| August 15 | The war ends. | |
| September 20 | Collapses from loss of blood. Relief team is disbanded. | |
| 1946 | January 28 | Appointed professor at Nagasaki Medical College. |
| July | Collapses at the Nagasaki Station. | |
| August | Finishes "Nagasaki no Kane". | |
| November 17 |
After preseuting the results of his research on "Atomic Illness and Atomic Medicine" at Nagasaki Medical College, he is confined to bed. |
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| 1947 | February 20 | Publishes "Sekai to Nikutai" to Sumisu Shinpu. |
| 1948 | January 17 | Finishes "Horobinu Mono wo". |
| March | Moves to the tiny house called Nyokodo ("As Yourself Hermitage"). | |
| March 25 | Finishes "Rozario no Kusari". | |
| April 30 | Finishes "Kono Ko wo Nokoshite". | |
| August | Retires on rest leave from Nagasaki Medical College and finishes "Seimei no Kawa". | |
| October 18 | Receives a visit from Helen Keller at Nyokodo. | |
| December | Receives the Kyushu Times Culture Award. Plants the "thousand cherry trees" in Urakami. | |
| 1949 | January | Publishes "Nagasaki no Kane" |
| March | Finishes "Hanasaku Oka". | |
| May 27 | Meets Emperor Showa at Nagasaki Medical College Hospital. | |
| May 30 | Receives a visit from a messenger of the Pope. | |
| August 1 | Receives commendation from the mayor of Nagasaki. | |
| September 30 | Retires from Nagasaki Medical College. | |
| October 30 | Publishes "Itoshi Ko Yo". | |
| December 3 | Decorated as an honorary citizen of Nagasaki. | |
| 1950 | May 14 | Receives a visit from a papal messenger and a gift of a rosary from the Pope. |
| June 1 | Receives commendation from Prime Minister Shigeru Yoshida and a silver cup from Emperor Showa. | |
| August | A preview of the movie Nagasaki no Kane is shown at Nyokodo. | |
| 1951 | April 22 | Finishes his last book "Otome Toge". |
| April 25 | Suffers internal bleeding in his right shoulder and becomes unable to write. | |
| May 1 | Enters Nagasaki University Hospital and passes away at 9:50 p.m. (43 years old). | |
| May 3 | Remembered in a Catholic funeral. | |
| May 14 | Remembered in a public funeral by Nagasaki City and buried at Sakamoto International Cemetery. | |
| 1952 | September 15 | "Otome Toge" is published. |
| 1957 | December 20 | "Nyokodo Zuihitsu " is published. |