In history, there are two types of primary documents. The first, which we might refer to as evidentiary documents because of their resemblance to trial evidence, are those documents that have been produced as part of a historical event. Evidentiary documents might include court proceedings or legal briefs, birth and death certificates, bills, receipts, family histories, genealogies. Often, evidentiary documents are used to make inferences about historical events, since they might not refer directly to those events. Use of evidentiary documents requires a sophisticated understanding of historiography and how such inferences are developed and supported. Chances are you will not be asked to analyze evidentiary documents yourself, except in advanced graduate classes. However, you will be asked to read secondary sources that analyze evidentiary documents. Consequently, you will need to understand how these documents are used in historical inquiry.
The second type of primary documents, which we might refer to as participatory or observational documents, are those documents that were written by a participant or observer of a historical event. Participatory/observation documents are most often first person accounts of the experiences of the writer. These might include diaries, newspaper articles, memoirs, letters, even histories written by participants or observers years after the events occurred. These are the primary documents you will come in contact with the most often in your research. While participatory/observation documents may appear to be factual because they were written by eye witnesses, they still need to be analyzed and interpreted. Every eye witness selects what information will be included and what will be excluded. Any eye witness account must be analyzed for bias. Even the most objective eye witness has a perspective that must be taken into account. An example of how participants in the same event bring their own perspectives to bear on those events are the two movies Letters from Iwo Jima and Flags of Our Fathers, both directed by Clint Eastwood. These movies show how American and Japanese troops brought different understanding to the Battle of Iwo Jima in World War II.
Identification of a document as “primary” may seem straightforward. However, whether a document can be considered a primary document hinges on the relationship between the document and your problem question. For instance, contemporary newspaper accounts about the sinking of the Lusitania by a German U-boat during World War I might not be a reliable primary document if you are asking questions about German navel strategy at that stage in the war. However, those newspaper accounts could be used as primary documents if you are asking questions about how civilian deaths affected American attitudes prior to U.S. entry into the war. In the first problem question, newspaper articles, even articles that quote eye witnesses, would be considered secondary documents because they were not written by participants or observers. In the second case, these same newspaper accounts would be considered primary documents because they directly reveal attitudes in the media.
Care should be taken when using primary documents. The writers of these documents did not always see them in such clear cut terms as our categories suggest, and often writers of memoirs and diaries will write about events they did not themselves experience. Just because a document was written contemporaneously to an event, does not make it a primary document. For instance, while Thucydides participated in the Peloponnesian War, his account, The Peloponnesian War, while one of our most important documents concerning that war, is not based exclusively on his experience. In point of fact, we have no idea how he gathered information about events he did not observe himself. Consequently, we use other methods to determine the veracity of his account, including careful analysis and interpretation of the text itself, comparing this account to other histories and determining whether his account agrees with archeological evidence.