Petals of Blood was Ngugi's first novel written whilst not in full-time education, instead written over a five-year period. Initially begun whilst teaching at Northwestern University in 1970, the writer continued to work on the novel after his return to Kenya, finally finishing the novel in Yalta as a guest of the Soviet Writers' Union. Ngugi was inspired to write the novel as a way of synthesizing the notion of a postcolonial nation, and a willingness to portray the agents of social change present in Kenya's change from British East Africa. Petals of Blood was the last of Ngugi's novels to be written first in English.
On 30 December 1977, shortly after the release of his play “I Will Marry When I Want,” Ngugi was taken into custody by law enforcement officials and held without charges for questioning. According to Patrick Williams, Ngugi was often criticized by detractors for “dragging politics into art.”
Despite the political tone to his novels, including Petals of Blood, Ngugi had avoided government interference until deciding to write in his native Gikuyu. After the release of Petals of Blood, Ngugi wrote and began work on a Gikuyu language play called 'Ngaahika Ndeenda' (I Will Marry When I Want). He was then arrested and detained on 30 December 1977, for crimes relating to his "literary-political" background. After this period, all of his novels would be written first in Gikuyu and later translated into English, a move understood to be a conscious decision to focus more strongly on the peasant workers of Kenya as inspiration for his novels.