The Treaty of Versailles in the mind of the Germans stabbed them in the back, especially the guilt clause that made them take blame for the First World War. Hitler capaitalized on these sentiments and used them to rally the German people.
Secondary Sources are materials that digest, analyze, evaluate and interpret information contained within primary sources or other secondary sources. Examples. 1  Autobiographies, memoirs, diaries, emails, oral histories.  Letters, correspondences, eyewitnesses.
The secondary source is the evidence of someone who was not present at the time of occurrence of the event e.g., books written by historians. The secondary source is also of great historical importance to the historians. Although secondary source is itself dependent on primary sources. A primary source may contain secondary information e.g., news papers are usually considered primary sources but the information provided by news paper is not all based on primary sources.