The Philippines were occupied by Japan during WWII, which produced many long lasting effects, both good and bad, on Filipino literature. Writing in Tagalog, the native Philippine language, was greatly encouraged, while writing in English was severely limited and often forbidden altogether. Furthermore, there was no freedom of speech or press, and censorship was widely practiced.
During WWII, Filipinos were forced to learn Japanese, so the Tagalog language began to incorporate Japanese slang and idioms in its vocabulary and literature. The Japanese form of poetry, Haiku, was also explored by Filipino writers during the occupation. Additionally, short stories came more into fashion. Since writing in English was severely limited by the Japanese regime, the vernacular Tagalog language became more widely utilized in literature. This exploration lasted beyond WWII, and helped Filipino writers embrace their native tongue. The Japanese occupation was fraught with fear and suffering for the Filipinos, and this is reflected in the literature of the time. Wartime Filipino literature is marked as being pessimistic and bitter. Owing to the extreme cruelty and hardship endured during the Japanese occupation, much Japanese influence was repudiated in the Philippines, leading many writers to embrace a more Western sensibility following the end of WWII.