The Metamorphosis thematically relates to WWI because it is all about change and transition. WWI was a transitionary time for everyone, especially after the war. People did not know what to do, just like in the Metamorphosis. Just like Gregor's family got used to him being a bug and missing from the family, people got used to relatives, friends and acquaintances missing. The entire World was in a state of transition but none more so than Britain and her inhabitants.