As your research paper takes shape you will find that you need background on people, places, events, etc. Do not just rely on some general survey for all of your background. Check the several good dictionaries of biography for background on people, or see if there is a standard book-length biography. If you are dealing with a legal matter check into the background of the judges who make the court decision and the circumstances surrounding the original incident or law. Try looking for public opinions in newspapers of the time. In other words, each bit of information you find should open the possibility of other research paths.