How are social groups, issues, and ideas represented in the film “The Book Thief”?

The idea of knowledge as a defense against ignorance and prejudice.

In the movie, knowledge is represented as a defense against hatred and intolerance. At the beginning of the story, we learn that Liesel Meminger is illiterate. When asked by her teacher to write her name on the blackboard, Liesel can only manage three Xs. It is Hans Hubermann, Liesel's adopted father, who teaches her how to read. The movie represents knowledge as a means of developing self-awareness and preserving self-identity. As Max Vandenburg argues, the procurement of knowledge reinforces our humanity:

Write. In my religion we're taught that every living thing, every leaf, every bird, is only alive because it contains the secret word for life. That's the only difference between us and a lump of clay. A word. Words are life, Liesel.

In the movie, Liesel's stories are encapsulated in the words of her journal. Her words inspire subsequent generations even after her death.

Social groups as an arm of totalitarian government, a vehicle for sanctioned violence, and a means of perpetrating destructive ideologies.

In the movie, Liesel and Rudy are members of Hitler Youth, the juvenile wing of the Nazi Party. One of the scenes shows a Nazi official presiding over the burning of books. In attendance are members of the German military, local citizenry, and Hitler Youth. The official gives an impassioned speech in German, and the locals express their support through enthusiastic shouts. The camera pans in on Liesel and Hans; both appear to be troubled by the Nazi exercise in totalitarian intimidation. 

Franz is seen taunting Liesel and Rudy; he threatens them and warns them against disobeying explicit orders to participate in the book burning. Meanwhile, the local citizenry sing patriotic Nazi songs as the books burn. The movie represents social groups like Hitler Youth as a means of securing the future of oppressive political structures. During WWII, the Nazis indoctrinated the members of Hitler Youth in Nazism and anti-religious ideologies. Members of Hitler Youth were encouraged to spy on their peers and to participate in violent acts against subversives (those who refuse to bow down to the dictates of Nazism). In the movie, Franz threatens to report Leisel and Rudy for being "up to something."

Issues of discrimination and persecution of minority groups as a horror and a stain upon a nation's honor.

In the movie, German soldiers routinely perpetrate horrific violence on defenseless Jews. The Jews are represented as the persecuted scapegoats of the Nazi regime. As the movie progresses, we learn that Leisel's adopted parents are sheltering Max Vandenburg, a Jewish fugitive. In WWI, Max's father saved Hans's life, so Hans feels obligated to Max. Rudy, suspecting that something is up, demands to know who Liesel's family is sheltering. Liesel's response is that she will put her adopted parents and herself in danger if she tells him the truth.

Eventually, Leisel does admit the truth to Rudy (he assures her of his loyalty), but their conversation is overheard by Franz. Franz tries to grab Leisel's journal, but Rudy throws it into the river. Enraged by this act of insubordination, Franz attacks Rudy. In the movie, youth violence testifies to the horrors endured by Jews and those who tried to help them during WWII. The movie represents the issue of religious discrimination as a dire threat to civilization.

The idea of death as an imminent fate for all, regardless of religion, race, or nationality.

Death speaks at the beginning of the movie; he assures us that, sooner or later, we will meet him, regardless of who we are. He tells us that death comes to all and that no one lives forever. In his characteristic bland tone, he informs us that panicking when death comes calling is a useless reaction. The movie represents death as a natural human experience. 

It also highlights death as the great equalizer on the field of battle. As Death watches the unfolding of WWII, he proclaims: "I met so many young men over the years who have thought they were running at their enemy, when the truth was, they were running to me." So, death is no respecter of persons, regardless of whether one fights to defeat evil or whether one fights on the side of evil.