Wicked Local On a sunny day, May 30, 1971, the Lexington Battle Green was once again full of soldiers. They did not wear red coats, nor did they fire muskets. Instead, these soldiers donned dark green fatigues and camouflage. They threw peace signs up into the air, and held signs calling for an end to violence overseas in Vietnam. Less than 24 hours later, hundreds of them were rounded and arrested up by police. It was, and still is, the largest mass arrest in Massachusetts history. Elise Lemire, a professor at Purchase College in New York and a Lincoln native, has spent the past decade researching the event and the factors that led to it for her new book, “Battle Green Vietnam.” It will be released later this spring.