Howard Zinn, the political activist and professor who authored the popular left-wing text A People’s History of the United States, died of a heart attack Wednesday in Santa Monica, Calif., the AP reports. He was 87 years old. Zinn described his book, initially published in 1980, as an alternative to mainstream history texts; more than one million copies have been sold. Zinn had his share of admirers in the entertainment industry: A People’s History was an inspiration for Bruce Springsteen’s Nebraska album and the 2007 documentary Profit Motive and the Whispering Wind; it was referenced by Ben Affleck and Matt Damon in the Good Will Hunting screenplay, and it appeared in the hands of a character on The Sopranos. Zinn, who lived in Auburndale, Mass., also penned the books The Southern Mystique, LaGuardia in Congress, and You Can’t Be Neutral on a Moving Train. You Can’t Be Neutral on a Moving Train was the title of a 2004 Damon-narrated documentary about Zinn. Zinn also narrated the Damon-produced documentary The People Speak, which was based on A People’s History and aired on the History Channel in December.