What is the context for this work?

Shanghai Girls is a novel published in 2009 by American author Lisa See. It is set in Shanghai, with the first chapter taking place in 1937, when the city was one of the richest and most fashionable in Asia. It is set against the background of World War II and the Second Sino-Japanese War, in particular the Battle of Shanghai, in which Japan invaded China. Later, as the two girls escape via Hong Kong to the United States, it addresses the lives of Chinese immigrants to California and the tensions between Chinese and Western traditions.