Discover, explore, and learn about the stories that make up the history of the United States.

AP US History Exam

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Primary Sources, Essays, and Videos

History by Era contains our historical content, organized by time period, with resources ranging from essays and videos by award-winning historians to featured primary sources with historical introductions, transcripts, and images, useful for research for your National History Day project, your AP lessons, and your American history papers. Learn how to navigate the History by Era section here.

You can find additional primary sources in the Gilder Lehrman Collection. Put your own search terms in the box in the left column here and select the filters below for era, theme, or object type.

If you have used a Gilder Lehrman essay, video, featured primary source, or Gilder Lehrman Collection document in a research paper, check out our Citation Guidelines for online resources.