Historical research often involves cycling between primary sources (the texts and other materials created in the historical period you are studying) and secondary sources (texts that attempt to explain, interpret, or narrate the past). You may start by learning about the period through your assigned (secondary source) readings, then spend time with some interesting primary sources, then search for secondary sources to help you understand and interpret the primary sources.
The research tools, databases, collections of sources, and suggestions on this research guide will help you find both primary and secondary sources.