About the author: Albert Klestadt (October 30, 1913 — April 4, 2006), born in Hamburg, Germany ( he was listed as a member of the Victorian Association of Jewish ex-Servicemen and Women). A obituary in the Sydney Morning Herald states,
Klestadt was working in Japan when war broke out. He provided the British with valuable intelligence on the Japanese navy before fleeing to Australia. On reaching Darwin, he was recruited by Australian intelligence services. He served with the Australian army in New Guinea and after the war helped to prosecute Japanese war criminals.
The Australian War Memorial records he was mentioned in dispatches.
About the diary: Provided the basis for the author’s book, The Sea Was Kind, (1960, New York, D. McDay Co.) The same obituary summarizes the story of his book:
Born in Hamburg, Klestadt’s mother taught him to sail on the Alster River. In 1935, aged 22, he left Germany to work for a German trading company in Tokyo.
However, in the early 1940s, with war preparations in Japan building, Klestadt turned his sailing and photography skills to good use by passing information on Japanese navy activities to British contacts.
In November 1941, he reported that all the Japanese ships in Kobe Harbour were painting out their distinctive markings with grey paint. It was a month before the Japanese attacked Pearl Harbour.
Realising that war was imminent, he headed for Australia. He had made it to Manila when the Japanese invaded and interred him.
Klestadt tricked his way out of captivity by producing his German passport, then bought an old trading boat, which he sailed solo through the southern Philippines, avoiding Japanese patrols.
The island people helped him by supplying food and directions. He also used charts torn from a Dutch atlas. He landed at Croker Island in December 1942, wearing his worldly possessions – a pair of torn shorts and an old shirt. Klestadt later wrote a book, The Sea was Kind, about his voyage.https://www.smh.com.au/national/he-set-sail-for-freedom-and-then-adventure-20060605-gdnoo1.html
According to him in his foreword,
The story is factual and is mainly taken from a diary and log kept by me between 8th December 1941 and 15th December 1942.https://archive.org/details/seawaskind010917mbp/page/n13/mode/2up
The Philippine Diary Project contains only the entries specifically mentioned as such by the author in his book: January 2, June 11 & 14, July 9, October 24, 1942