The novel is set in the 1970s but frequently flashes back to Naomi's childhood during the 1940s. After the attack on Pearl Harbor, Naomi's family, along with thousands of other Japanese Canadians, is forcibly removed from their homes and sent to internment camps. The family is separated, with Naomi and her brother Stephen sent to live with an aunt (Obasan) and uncle in a remote, desolate area of British Columbia, while their mother returns to Japan and their father dies.
"Obasan" is a powerful exploration of memory, silence, and the effects of historical injustices on individuals and communities. It sheds light on a dark chapter in Canadian history, highlighting the resilience and suffering of those who were unjustly persecuted.