The Train
The train that the novel's main characters travel on to escape their life is a symbol of escape. Without the train, they would have been condemned to life in prison (or perhaps even death) after being chased and prosecuted in Russia. With the help of the train, they can start a new life free from trouble in Siberia.
Russia
The novel's setting, the country of Russia, is a symbol of oppression. Because of its dictatorial style of government, Russia doesn't allow people to be fully themselves and engage in demonstrations and other free activities. That forces the novel's main characters to flee on a train to Siberia, where they hope they can be free and live authentic lives.
Moving forward
The most significant motif is moving forward. The novel's main characters constantly move forward and try to escape the clutches of the Russian government, which is trying to capture them. If they ever stop, things will go badly for them.
Language
Language—Russian and French—is symbolic of the way that people interact with each other. In the case of Eastbound, the characters are not able to communicate with each other in a common language, forcing them to adopt a new language (winks, nods, and other kinds of pantomimes). This new language illustrates how resourceful people are.
