Reference resources are a great place to begin your research. They can help you define terms as well as to find background information about a topic, a chronicle of its history, theories, key people and sometimes a bibliography of additional sources.
There are many different types of reference sources, which include dictionaries, encyclopedias, thesauri, bibliographies, handbooks, style manuals to name a few.
The Wiley Blackwell Dictionary of Modern European History since 1789
This four volume set largely focuses on British and North American perspectives of the enlightenment.
Longman Companions to History (Series)
Stauffer Library (call number varies)
Good starting point for research to a major area of historical study.
Check Omni under title, Longman Companions to History, to get a complete list of titles. Go to Advanced Search....
Oxford Bibliographies offers peer-reviewed annotated bibliographies which identify the best available scholarship across a wide variety of subjects.
It covers classic and up-to-date monographs, collections, datasets, articles and web-sites. Each article includes an introduction written by a top scholar in the field.
There are essays on the French Revolution, Industrialization, Russian Revolution, Cold War, Nations and Nationalism to name a few. .