Spanning almost fifty years, Series II contains a wide variety of correspondence from strangers, acquaintances, colleagues and publishers. Much of the material could be classified as fan mail although there are critical letters as well. Many of the correspondents are involved in progressive causes championed by Zinn and the letters often reflect the personal experiences of those for whom Zinn's writings resonate. There are also requests for job or school references as well as letters asking for Zinn's participation in a variety of events and projects. Some of the correspondence is neither to nor from Zinn, but appears to have been shared with him by others.
Zinn's annotations appear on some of the material and there are retained copies of a few of his responses. In a good number of instances, related items are included with the incoming letters (e.g., articles, reviews, clippings). Some well-known persons may be found within this series. Examples include Bill Moyers, Pete Seeger, Herbert Aptheker, Eqbal Ahmad and Noam Chomsky.
In addition to general correspondence, the series also contains two specific groups of letters. The first, reflecting Zinn's interest in justice and the rights of the incarcerated, consists of correspondence with prisoners; some are well-known, such as Kathy Boudin and Mumia Abu-Jamal. The second group of letters involves students, many at the secondary school level. A number of teachers either introduced Zinn writings in their class or invited him to visit and speak to the students. In both cases, the students were asked to write to Zinn with their reactions, questions or criticisms.