" From 1929 to 1933, [age 25-29] I lived almost continuously in Berlin, with only occasional visits to other parts of Germany and to England. Already, during that time, I had made up my mind that I would one day write about the people I’d met and the experiences I was having. So I kept a detailed diary, which in due course provided raw material for all my Berlin stories. [from preface] "
― Christopher Isherwood , The Berlin Stories