All Quiet at the Western Front is about people who are trying to deal with the war: soldiers, commanders, civilians, prisoners of war, and fugitives.
One of the most prominent themes is the way of adapting to harsh conditions of those men who became soldiers while being very young, like Paul and his schoolmates. They know no other way of life, and all they can do is kill and die.
This book also deals with the issues of physical and spiritual survival.