A fundamental principle of writing history is that you must cite the sources of all your information that is not "common knowledge." Citation serves the following functions.
1. It gives credit where credit is due. It's okay to borrow ideas (whether paraphrased or in direct quotes) from others as long as you acknowledge it. Failure to do so can result in a charge of splagiarism, a serious academic offense that could get you expelled from high school or college and/or ruin your reputation for honesty. If you haven't done so yet, please read the department's Plagiarism Policy.
2. It allows your reader to find the information you used if they want to go deeper into that topic or verify/challenge your conclusions.
3. It gives legitimacy to your arguments. It says to the reader: these facts exist--go see for yourself--or I'm not the only one who has thought of this, these other smarter people thought so too.
Citations follow certain conventions, which are different in different disciplines. Every citation contains three basic elements:
You are letting your reader know who wrote or created the document (if the author is known), what the source is called, and where you found it (so that the reader can go find it).
The most difficult kind of citation and one you will often have to use is the "source within a source" citation. Our library has tons of books that are collections of primary documents or historical essays. You need to first cite the author and title of the original document. Then you have to cite the title and editor of the collection of documents along with all the other publication information.
The Phillips Exeter Academy History Department requires Chicago or Turabian style (more or less the same thing). I have made a Citation Guide showing how to cite some of the more common sources. English departments usually require MLA style. You can download a brief guide to Chicago/Turabian styles. It shows you how to format the types of sources you will most often be using.
These are the requirements for formal research papers. For other papers, different history teachers will have different requirements.
Mr. Jordan's citation requirements for all essays other than research papers:
1. Do not use parenthetical in-line citations (like this). Put your citations in footnotes.
2. Number citations sequentially. Each citation gets a new number, even if you are citing the same source.
3. For sources that I have given you, use the author's last name and a page number like so: Davidson, 23. When there are more than one documents written by the same author, include the title of the document like so: Lincoln, "Gettysburg Address," 24. These are the Chicago/Turabian formatting styles for citations after the first.
4. If you are using a source other than something I've assigned, you need to include a complete reference. Note: a URL is not a complete reference. For example:
Wikipedia contributors, "Abraham Lincoln," Wikipedia, The Free Encyclopedia, https://en.wikipedia.org/w/index.php?title=Abraham_Lincoln&oldid=870406291 (accessed November 26, 2018).