The book is introduced with the character/narrator death, which immediately presents the strong truth that mortality is very present in the lives of each character. Throughout the novel, there are multiple deaths of prominent characters, which reaffirms the presence of mortality. On top of the individual characters experiencing death on a personal level, the novel takes place during World War II, and more specifically during the Nazi reign. Because of this, death and genocide are nearly omnipresent in the novel (which is illustrated by the omnipresent narrator being death). Death is presented in a manner that is supposed to make it less distant and threatening. Since every death (and other event) is narrated by the personification of death, dying is presented in less of a chaotic and uncontrolled manner. Since Death narrates and explains the reasons behind each character's destruction as well as explaining how he feels that he must take the life of each character, death is given a sense of care rather than fear. At one point, Death states "even death has a heart," which reaffirms that there is a care present in the concept of death and dying. 
Identity is present in the novel in two main ways. First, in regard to Hitler's reign characters in the novel are immediately identified as either Jewish or non-Jewish. This identity is enforced through political tactics and ties in to the theme of mortality. Secondly, Liesel is trying to develop and find her identity through the majority of the novel, which creates a strong thematic element as the story progresses. Eventually writing and reading become major tools through which Liesel develops her identity. When analyzing these two ways that identify presents itself in the novel, one possible analysis is that identity can be seen on a macrocosm level and microcosm level. On the macrocosm, identity is defined by outside sources based on external factors. This is represented by the Nazi party separating people into Jewish and non-Jewish categories. This type of identity ironically strips all people of any sort of true and individual identity. On the other hand, there is the microcosm level of identity that is represented in the novel. This is seen in the development of each individual character as they grow in self, knowledge, love, and skill. Because of the dynamic presented in each individual, their personal identity is presented to the reader. When juxtaposing these two analyses, one result of the way the theme is used in the novel is to suggest that identity is a power that a person can yield.
Language, reading & writing
These three things are present as tools of freedom and expression throughout the story. They are symbolic elements that provide liberation and identity to the characters who are able to wield their power. Furthermore, they define the novel in its entirety since Liesel as a character collects books and writes her own at the conclusion of the novel. In conjunction, these three items can also provide a framework for Liesel's coming of age. In the beginning of the novel, she obtains a book at her brother's funeral that she is not able to read. As the story progresses, she slowly learns how to read and write because of the tutelage of her foster father Hans. By the end of the story, her character arc is heavily defined by her ability to read and write. The development of her literacy ability mirrors her physical growth and strength developing over the course of the story. Language, reading, and writing also serve as social markers. The wealthy citizens in the story are often portrayed as owning their own libraries and being literate, while the poor characters are illiterate and do not own any books. Lastly, the Nazi party historically burned books, and this practice is represented in the novel itself. Symbolically, Liesel's continuous rescue of the books that the Germans are attempting to burn represents her reclaiming freedom and fight against being controlled by the Nazis.
In the midst of the damage that war, death, and loss have caused Liesel and the other characters in the book, love is seen as an agent of change and freedom. Liesel overcomes her own traumas by learning to love and be loved by her foster family and her friends. In the beginning of the novel, Liesel is traumatized not only by the death of her brother and her separation from her only family, but also because of the larger issues regarding war-torn Germany and the destruction of the Nazi party. As Liesel's foster father Hans develops a relationship with her, healing and growth are seen as a direct result. This pattern is reflected with the relational dynamic between the Hubermann family and Max. In the midst of governmental policies and the resulting destruction that force stringent opinions on who is worthy of love and acceptance, the Hubermann's relationship with Max perpetuates and therefore defies the Nazi's regime. Furthermore, the love that Max and Liesel develop through their friendship creates a strong contrast to the hate that is the backdrop of the story because of the war and the Nazi ideals. The theme of love also intertwines with the themes of identity and language/reading because all of these themes have the purpose of providing freedom and power in the midst of chaos and control.