How are themes of identity, dislocation, and history portrayed throughout the novel?

Identity, dislocation, and history are portrayed vividly throughout Teju Cole's Open City. The main character, Julius (a young, Nigerian graduate student in psychiatry), routinely walks around the city as a means to decompress from his mentally taxing job. The novel's progress mirrors Julius' progress through graduate school, though the events of the novel depict primarily his free time.
Julius' identity as a German-Nigerian is important to him. He takes a trip to Brussels, ostensibly in search of his only remaining German grandmother. He spends much of his time in Belgium alone, and, ironically, he lies about his identity to a woman with whom he has a sexual encounter. This demonstrates the disjunction between sexual and emotional intimacy.
Another moment charged with the issue of identity is when Julius sees a group of black people assembled in Brussels, and he assumes the group is from the Congo (a former Belgian colony), though they are in fact Rwandans (a group that experienced harsh genocide as living memory). Identity in Cole's novel is both deeply personal and also misleading.
Dislocation is a theme witnessed in the novel primarily through accounts of colonial periods across the globe. One of Julius' patients wrote a novel about colonial New York, and another wrote a book about a Dutch settler who killed many Native Americans. Julius thinks that his patient's intense academic study of these horrific events contributes to her depression. During his trip to Brussels, Julius also learns how the French have overwhelmed the native Flemish population in Belgium. Colonial rule is, as a rule, viewed with a critical lens throughout the novel.
History, too, is a primary concern for Julius. Julius is attracted to discovering his only living grandmother in Brussels. As Julius is an introspective individual, he contemplates his own family history, told through flashbacks at punctuated intervals throughout the novel. He primarily remembers his grandmother and disobeying his parents' orders not to drink Coke (for which, as an adult, he has no taste).
In Open City, Julius feels that places are imbued with meaning owing to their history. Two prominent spots are a slave burial ground in lower Manhattan, commemorated by a nondescript sculpture. In the closing scene of the novel, Julius is invited aboard a yacht, from which vantage point he contemplates the Statue of Liberty--the iconic and historic landmark for immigrants to America. Seeing the light of the statue, many birds die flying toward it. History thus imbues various places--and the novel as a whole--with poisoned memories.