Xavier March is a fictional character from the novel "Fatherland" by Robert Harris. Set in an alternate history where Nazi Germany won World War II, March is a detective in Berlin. He investigates a murder that leads him to uncover a conspiracy that challenges the regime's narrative. As a character, March embodies the struggle for truth in a repressive society. His journey reflects themes of morality and resistance against totalitarianism. The novel explores the implications of a world shaped by Nazi ideology and the impact of World War II on individual lives.