The Moratorium to End the War in Vietnam was a massive demonstration and teach-in across the United States against the United States involvement in the Vietnam War. It took place on October 15, 1969, followed a month later, on November 15, 1969, by a large Moratorium March in Washington, D.C.

A teach-in is similar to a general educational forum on any complicated issue, usually an issue involving current political affairs. The main difference between a teach-in and a seminar is the refusal to limit the discussion to a specific time frame or a strict academic scope. Teach-ins are meant to be practical, participatory, and oriented toward action. While they include experts lecturing on their area of expertise, discussion and questions from the audience are welcome, even mid-lecture. "Teach-ins" were popularized during the U.S. government's involvement in Vietnam. The first teach-in, which was held overnight at the University of Michigan in March 1965, began with a discussion of the Vietnam War draft and ended in the early morning with a speech by philosopher Arnold Kaufman.