Zinn's A People's History of the United States is written in open and direct opposition to the commonly held American history.
He begins in the year 1492 by examining the American attachment to Christopher Columbus (which was considerably stronger in 1980 when this book was published). Zinn notes that American historians and textbooks tend to gloss over the facts about Columbus's involvement in systematic genocide. He explains the events through the lens of the Native American Arawak tribe. He discusses the breadth and sophistication of Native societies, and the absolute decimation that began with Columbus and continued on. He shows that Columbus was aware at the time, and he cites Columbus's own journal which explains horrific violence against the natives.
He discusses African slave trade and the involvement of the American colonies in that slavery. He also observes here that racism was not a leading factor in American slavery—money was. He continues onward to discuss Bacon's Rebellion. He argues that it was class warfare that led to that rebellion.
In the chapter, 'Tyranny is Tyranny,' Zinn offers one of his most controversial ideas: That the Founding Fathers of the United States were actually all wealthy businessmen who used the Revolution as a way of getting what they wanted economically. He notices that the French supplied the majority of American Revolutionary weaponry, and that many people did not support the Revolution, and he observes that for no clear reason, history tends to paint those people as villains.
He continues by addressing women's history, acknowledging nearly two dozen important women of history, including Sojourner Truth, but also including many women who should be well-known but aren't, because they're women after all, and because of the times, they were excluded from the historical evidence. He draws the reader's attention to the abominable history of how the United States secured it's Southwestern territory—by invading a nation to conquer it, and by killing a lot of people. He argues that for this, Polk is an imperialist.
He treats the Civil War next, discussing the difficult nuances of abolition in America. He shows that the way historians depict these issues are not colored properly by all the economic interests that were served along the way—because companies and industries already held sway in America (Zinn believes).
After the Civil War, he discusses "The Other Civil War," the division of the United States across the political lines of unionization and industry. He discusses what historians often forget—all the minor political parties along the way who were arguing for socialism or populism.
Then he turns forward to the Great War, the Great Depression, WWII and the modern era. He says that socialism and anarchism were always healthy political parties in the United States throughout those eras, but that they were ignored and painted as heretics.
He discusses the truth of the Jazz era showing that the lavish wealth of the few came at dear costs to those on the lower castes. He shows that the Communist Party desperately tried to help the poor during that time, argues Zinn. He covers the Jim Crow laws as a continuation of racial hatred. He shows the bombings of Nagasaki and Hiroshima were completely unnecessary, and he explores the implications of our historical opinions about that. Many times during that war, the government made decisions and then swayed public opinion away from criticism. He describes the growth of the Military-Industrial Complex in American Capitalism.
Continuing forward, he explores the authentic, legitimate value of social movements that happened in the underground. He discusses the historical time of Nixon's presidency, and what that represents about American government moving forward. He discusses the horror and injustice of the Vietnam War.
Then, Zinn moves into the Reagan-Bush era, and the Clinton presidency. He ends by criticizing Clinton directly, for his failure to seek justice on these topics: The Waco Seige, the OKC bombing, the NAFTA, American involvement in Afghanistan and Sudan, Iraq, and even the Rwandan Genocide. Lastly, he discusses the War on Terrorism, the Bush Jr presidency, and the narrative that Arab terrorists were offended by freedom. He argues that this narrative is stupid—he argues that 9/11 didn't happen because the Muslims hate freedom.