Confirm background facts (such as names, dates, places) and determine what is "common knowledge" information (i.e facts that have enough universal agreement they do not need citations) about your topic using Reference books.
Reference books are also an efficient way of informating yourself about historical context surrounding your topic and about significant people or events related to your topic.
Reference books include biographical dictionaries, historical dictionaries, encyclopedias, atlases, and statistical summaries.
This book, assigned on the HIST 174 syllabus, includes its own reference appendices: a glossary, biographical sketches, chronology and suggested readings bibliography.
Many Reference books include bibliographies that suggest important secondary studies. Bibliographies, footnotes and suggested readings sections of scholarship you read in class can point you in the direction of appropriate starting places for your individual research as well.