Once you have selected your research topic, you should also make a research plan. The usual starting point is to identify the main currents of thought on your topic. Naturally, you need to know which scholars have taken up this topic, what their main arguments are, and how our understanding of the subject has changed with shifts in the predominant methodologies and theoretical perspectives. In answering these questions, you will use secondary sources (the published work of scholars specializing in the topic); this is also termed the secondary literature on the subject. You will situate yourself in relation to the secondary literature on your topic. Does your analysis agree with previous scholarship, or are you offering a new interpretation?
If you are unfamiliar with your subject area, it will be very helpful to begin with a source that summarizes the main events or circumstances and also describes the context. This strategy also helps you verify that at least some research has already been done on your topic--it would be very difficult to cover all the background and conduct original research on your topic without any direction from other scholars, all in a single semester!
Examples of sources that provide broad overviews:
Secondary sources are the published work of scholars specializing in the topic. Secondary sources include scholarly books, articles, and essays (both analyses by contemporary scholars as well as older analyses), surveys, criticism, comparative studies, reference sources, and works on theory and methodology; this is also termed the secondary literature. Eventually you will need to decide which interpretation makes the most sense to you and seems consistent with your primary sources, or if you wish to offer a new interpretation.
When we talk about secondary sources, most of the time we are referring to published scholarship on a subject, rather than supplemental material (bibliographies, encyclopedias, handbooks, etc.). Secondary literature is published in both book form and as articles in periodicals, either in print or digital format. (Digital format includes both reproduction of print material online and original e-text.) This scholarship is analytical and interpretive. It may synthesize the work of other scholars to present a totally new interpretation. More likely, it offers a new reading of previously analyzed sources or presents an analysis of previously unknown sources.
Hence, you use secondary sources to identify the main currents of thought on your topic. Which scholars have taken up this topic and what were their main arguments? How has our understanding of the subject changed with shifts in the predominant methodologies and theoretical perspectives in the historical profession?
To identify secondary literature, you can do subject searches in the online catalog to find books or subject searches in article databases to find articles; article databases may list books as well a articles from journals.
You can also look for review essays, in which a scholar who specializes in the subject analyzes recent scholarship; you may find more lengthy treatments of the topic published as chapters in collections, journal articles, or even monographs; you can read about the topic in a subject encyclopedia and look at the bibliography at the end of the entry; and you can find a major work of scholarship on the topic and follow up on the sources used by the author (footnote tracking).
Most of the time you will find the secondary literature you need by using the online catalog, the appopriate article databases, subject encyclopedias or bibliographies, and by consulting your instructor.
You've identified some of the main currents of thought on your topic, and you've begun to reflect on your findings: