Zimmermann received his undergraduate, graduate and doctorate in history at the Hebrew University of Jerusalem where he also currently works.

In 2015 he was interviewed and filmed for the documentary The Essential Link: The Story of Wilfrid Israel by Yonatan Nir, in which he offered more angles to explain why Wilfrid Israel's story did not receive the expected public attention.

Zimmermann was taken to court several times and cited for defamation in the wake of comments he made in 1995 regarding comparisons that he thought might be drawn between settlers in Hebron and Nazi youth, in the wake of Baruch Goldstein's Cave of the Patriarchs Massacre.

[3] In 2002, Zimmermann sued Haaretz for libel after it published an unflattering mention in an article authored by a former student, who claimed Zimmermann drew comparisons between Israel and Nazism while being supported financially by Germany.

[3] In 2004, the lawsuit was, however, dismissed, with Zimmermann having been admonished by the judge for making controversial analogies and yet, at the same time, not accepting criticism of his views.