Historian's use of Primary Sources

The first thing that historians must be cautions of when using primary sources such as letters from the world wars, is the amount of censoring that was done to the letters in question. During the first and second World Wars soldiers would communicate to their families through letters, postcards and the occasional telegram. Although this was the best way to communicate with family under the circumstances, it was also a very easy way for enemy lines to intercept letters and gain valuable information. For this reason there were very strict rules as to what soldiers could put in their letters home. The rules included; not writing of future or past plans, locations, transportation, future and past operations, deaths before they are released by authorities, writing in code and other regulations. These rules limited soldiers ability to speak of the war itself, or they would excluded valuable information that then historians would unintentionally exclude from their own writing. Not only were soldiers under strict regulations as to what they could include in their letters, they also would sugar coat events, and things that had happened to them so as not to upset or worry their families and friends.